ACUS48 KWNS 160948
SWOD48
SPC AC 160947

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CST Mon Dec 16 2024

Valid 191200Z - 241200Z

...DISCUSSION...
Medium range guidance is in fairly good agreement that an amplified
but progressive upper level pattern will overspread the CONUS during
the Day 4-8 period. A shortwave trough over the northern Plains
early on Day 4/Thu will deepen and spread east over the eastern half
of the CONUS through Day 6 or 7/Sat or Sun. Meanwhile, an amplified
upper ridge will build over the western states and spread east into
the Plains during this same time period. Spread among guidance
increases around Day 6-8/Sat-Mon, but still indicates that another
upper trough will emerge over the Plains and Midwest late in the
period.

A surface cold front will move south and east into the Gulf of
Mexico and offshore the Atlantic coast on Thursday. This will clear
out any lingering boundary-layer moisture and persistent offshore
trajectories will mostly preclude much thunderstorm potential for
most of the forecast period. The exception may be on Day 7-8/Sun-Mon
as lee troughing allow for southeasterly flow to return across the
western Gulf and TX, bringing modest moisture northward across
southern/central TX. Nevertheless, severe-thunderstorm potential
appears low throughout the forecast period.

..Leitman.. 12/16/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 170934
SWOD48
SPC AC 170933

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CST Tue Dec 17 2024

Valid 201200Z - 251200Z

...DISCUSSION...
Strong surface high pressure over the central U.S. and a prior cold
front intruding into the southern Gulf of Mexico will result in a
dearth of boundary layer moisture across much of the CONUS through
at least Day 6/Sun. As a result, thunderstorm chances will be low.
Toward the end of the period, some forecast guidance suggests lee
troughing will allow southeasterly low-level flow to bring modest
Gulf moisture northward across TX. This may result in some increased thunderstorm chances across south/central TX on Day 7-8/Mon-Tue.
However, severe-thunderstorm potential will remain low during the
Day 4-8 time frame.

..Leitman.. 12/17/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 180940
SWOD48
SPC AC 180939

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CST Wed Dec 18 2024

Valid 211200Z - 261200Z

...DISCUSSION...
Strong surface high pressure and a dearth of boundary-layer moisture
will preclude severe thunderstorm potential on Days 4-5/Sat-Sun.

By Day 6/Mon, medium range forecast guidance shows a series of upper
shortwave troughs shifting east from the Rockies to the MS Valley
through Day 8/Wed (Christmas Day). In response, lee
troughing/surface low developing is expected over parts of the
southern Plains. Increasing southerly low-level flow will support
modest northward transport of Gulf moisture across parts of TX into
OK, and eventually the Lower MS Valley near the end of the period.
While there is still quite a bit of spread with regards to
intensity, location, and timing of these features, increasing
thunderstorm activity is expected Day 6-8/Mon-Wed across the
southern Plains vicinity. While uncertainty is high, if timing and
overlap of key features comes to fruition, some severe risk could be
possible over the upcoming Christmas holiday period.

..Leitman.. 12/18/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 190846
SWOD48
SPC AC 190845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0245 AM CST Thu Dec 19 2024

Valid 221200Z - 271200Z

...DISCUSSION...
Strong surface high pressure and a dearth of boundary-layer moisture
will limit thunderstorm potential on Day 4/Sun. Starting Day 5/Mon,
a progressive upper level pattern is forecast, and a series of
shortwave trough will migrate across the Plains to the Midwest. As
this occurs, surface lee troughing will support south/southeasterly
low-level flow across the southern Plains and the Gulf of Mexico.
Modest boundary-layer moisture will being to return northward across
TX toward OK by early next week, and eventually into the Lower MS
Valley by mid to late in the week. Large spread remains regarding
the timing and intensity of these features across the south-central
U.S. However, thunderstorm potential will begin increasing starting
Day 5/Monday across OK/TX, shifting east with time through Day
8/Thu. Some severe-thunderstorm potential could accompany this
activity, but predictability is too low at this time to include
outlook delineations at this time.

..Leitman.. 12/19/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 200905
SWOD48
SPC AC 200904

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0304 AM CST Fri Dec 20 2024

Valid 231200Z - 281200Z

...DISCUSSION...
A more active southern-stream pattern should evolve next week, with
several lower latitude troughs crossing the southern tier along with
some northward increase in low-level moisture across parts of Texas
to the Lower Mississippi Valley and Gulf Coast. One such shortwave
trough should influence increasing thunderstorm potential across
east/southeast Texas on Tuesday/Day 5. Some severe risk could
materialize, but it appears that overall buoyancy will be weak with
the severe potential currently expected to be relatively marginal
and isolated in nature.

An additional focus for increasing deep convective potential will be
into the Thursday/Day 7 and Friday/Day 8 time frame. This will be as
a secondary upper trough emerges from the Southwest deserts. This
could lead to some severe risk in a corridor from east/southeast
Texas and ArkLaTex to Lower Mississippi Valley. However, there is
some uncertainty regarding moisture/destabilization given the
potential influences of the preceding shortwave trough and cold
front. Forecast uncertainties at this time frame precludes any 15%
outlook areas.

..Guyer.. 12/20/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 210923
SWOD48
SPC AC 210922

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CST Sat Dec 21 2024

Valid 241200Z - 291200Z

...DISCUSSION...
A more active southern-stream pattern is expected next week with
several lower latitude troughs crossing the southern tier, along
with some northward increase in low-level moisture across parts of
Texas to the Lower Mississippi Valley and Gulf Coast. On Tuesday/Day
4, one such shortwave trough should influence increasing
thunderstorm potential across south-central to east/southeast Texas.
Some severe risk could materialize Tuesday, but it appears that
overall buoyancy will be weak with the severe potential currently
expected to be relatively marginal and isolated in nature.

An additional focus for increasing deep convective potential will be
into the Thursday/Day 6, Friday/Day 7, and Saturday/Day 8 time
frame. This will be as a secondary upper trough emerges from the
Southwest deserts and moves toward the Deep South. This could lead
to a severe risk in a corridor from east/southeast Texas and the
ArkLaTex to Lower Mississippi Valley. While some severe storms will
be possible, perhaps especially Thursday/Day 6, there is lingering
risk magnitude uncertainty related to moisture/destabilization given
the potential influences of the preceding shortwave trough and cold
front. Forecast uncertainties at this time frame precludes any 15%
outlook areas.

..Guyer.. 12/21/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 221002
SWOD48
SPC AC 221000

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CST Sun Dec 22 2024

Valid 251200Z - 301200Z

...DISCUSSION...
A moderately amplified and more active/progressive southern-stream
pattern is still expected later this week, along with a general
northward fluctuation of low-level moisture across parts of Texas to
the Lower Mississippi Valley and Gulf Coast.

After a day of little or no severe-weather potential on Christmas
Wednesday/Day 4, severe risks are expected to increase into Days 5-7 Thursday-Saturday. A secondary upper trough is expected to emerge
from the Southwest deserts and moves toward the Ozarks/Deep South.
This could lead to at least a low-end multi-day severe risk in a
corridor from east/southeast Texas and the ArkLaTex to Lower
Mississippi Valley. In particular, Thursday/Day 5 could ultimately
warrant Slight Risk-caliber severe probabilities across
east/southeast Texas, especially if the more southern and more
severe-favorable ECMWF model runs become more apparent.

..Guyer.. 12/22/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 230956
SWOD48
SPC AC 230955

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CST Mon Dec 23 2024

Valid 261200Z - 311200Z

...DISCUSSION...
Severe-weather potential is still expected for Days 4-6
Thursday-Saturday, as an upper trough emerging from California and
the Southwest deserts moves toward the Ozarks/Deep South by
Thursday/Day 4. At least a low-end multi-day regional severe risk is
expected across south-central and east/southeast Texas towards parts
of the ArkLaTex, and possibly the Lower Mississippi Valley. In
particular, Thursday/Day 4 could ultimately warrant Slight
Risk-caliber severe probabilities across south-central to
east/southeast Texas although guidance variability persists, while objective/machine-learning guidance generally also persist with
sub-15 percent probabilities.

..Guyer.. 12/23/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 241000
SWOD48
SPC AC 240959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Tue Dec 24 2024

Valid 271200Z - 011200Z

...DISCUSSION...
At least some severe-weather potential is expected across East Texas
and the Deep South for Friday/Day 4 and Saturday/Day 5. On
Friday/Day 4, a secondary shortwave trough may evolve across the
southern Plains in the wake of the shortwave trough related to
Thursday's/Day 3 severe potential. While some severe storms could
occur across east/southeast Texas toward the ArkLaTex on Friday/Day
4, details of available buoyancy are uncertain, especially given the
short periodicity between these mid-level systems. Similarly, a
severe storm risk could shift eastward toward the Lower
Mississippi/Mid-South on Saturday/Day 5, but confidence in 15+
percent probabilities is currently limited. Severe storm potential
is then expected to be relatively low into Days 6-8 Sunday-Tuesday.

..Guyer.. 12/24/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 251003
SWOD48
SPC AC 251002

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0402 AM CST Wed Dec 25 2024

Valid 281200Z - 021200Z

...DISCUSSION...
At least some severe-weather potential is expected this weekend
including Saturday/Day 4 and possibly Sunday/Day 5. On Saturday/Day
4, the next in a series of shortwave troughs is expected to shift
eastward over the southern Plains and Ozarks. Given the influence of
the upper-level system and proximity of low-level moisture, at least
some severe risk appears likely across the Lower Mississippi Valley
to Tennessee Valley, including parts of Louisiana to Mississippi and
Alabama. However, the short periodicity in the wake of the prior
shortwave trough, plus the possibility of extensive early day
precipitation, currently limits confidence in placement of a 15+
percent severe risk area, although Slight Risk-caliber potential may
become more evident in future outlooks.

The severe-storm risk should shift eastward across the Southeast
States on Sunday/Day 5, but probably on a more isolated/marginal
basis. Severe storm potential should be relatively low early next
week into Days 6-8 Monday-Wednesday.

..Guyer.. 12/25/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 261011
SWOD48
SPC AC 261010

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0410 AM CST Thu Dec 26 2024

Valid 291200Z - 031200Z

...DISCUSSION...
At least some severe-weather risk is expected on Sunday/Day 4 across
the Southeast States as an upper trough shifts east-northeastward
from the Ohio/Tennessee Valleys toward the Appalachians. Very strong
deep-layer winds will overspread the region, but guidance
variability exists regarding the availability and
north-northeastward extent of minimal buoyancy, especially with GFS/ECMWF-related guidance depicting the possibility of considerable
scattered convection ongoing Sunday morning. Regional areas
including northern Florida into southern/eastern Georgia and parts
of the Carolinas will continue to be reevaluated in subsequent
outlooks as far as Sunday's severe potential, but at least
some/low-end severe risk seems probable even with these instability uncertainties.

Thereafter, severe-weather potential early next week is currently
expected to remain low.

..Guyer.. 12/26/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 271000
SWOD48
SPC AC 270958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Fri Dec 27 2024

Valid 301200Z - 041200Z

...DISCUSSION...
Overall severe-weather potential should remain relatively low next
week, largely attributable to a frontal intrusion into the Gulf of
Mexico on Day 3/Sunday. Air mass modification/modest-caliber
elevated moisture return may occur Monday/Day 4 from the western
Gulf of Mexico into southeast Texas and Lower Mississippi Valley, as
a shortwave trough amplifies over the southern Plains and Ozarks. A
few strong storms cannot be entirely ruled out late Monday, but such
potential should remain low overall. Additional low-level moistening
will occur across parts of the Gulf Coast and Southeast on
Tuesday/Day 5 ahead of the amplifying mid-level trough and
associated cold front, but again, overall severe potential should
remain low given the moisture and instability limitations.

Convective potential should be very low, perhaps virtually nil,
between Wednesday-Friday Days 6-8 as cold/stable continental
trajectories prevail east of the Rockies.

..Guyer.. 12/27/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 280958
SWOD48
SPC AC 280957

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Sat Dec 28 2024

Valid 311200Z - 051200Z

...DISCUSSION...
A strong upper trough and associated surface low/cold front will
move towards the Mid-Atlantic and southeast U.S. coast Tuesday, and thunderstorms will be possible within a weakly unstable warm sector
as large-scale ascent increases during the day. Confidence in the
potential for stronger storms is low given the spatially confined
area and expected weak destabilization.

During the remainder of the week and, despite some model/ensemble
variability, there is general agreement on an eastern CONUS upper
trough and a ridge across the western U.S. This pattern does not
favor substantial/rapid moisture return in the wake of the prior
cold frontal passage, and overall thunderstorm chances will be very
low to nil Wednesday through Saturday.

..Bunting.. 12/28/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 290949
SWOD48
SPC AC 290947

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CST Sun Dec 29 2024

Valid 011200Z - 061200Z

...DISCUSSION...
A broad/expansive upper-level trough will persist over much of the
eastern U.S. during the upcoming week, while a ridge of high
pressure will extend over the western portion of the CONUS. A series
of surface high-pressure systems will result in generally dry/stable
conditions and minimal to no chance for thunderstorms through
Friday/Day 6. Towards Saturday/Sunday (Days 7 and 8), guidance is
varied but does suggest some increase in thunderstorm potential over
the south-central U.S. as an impulse over the western U.S. moves
east of the Rockies. Uncertainty is high at this relatively extended
range on the timing and degree of amplification of this feature, and
therefore the overall potential for thunderstorms remains low with
this outlook.

..Bunting.. 12/29/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 300933
SWOD48
SPC AC 300931

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CST Mon Dec 30 2024

Valid 021200Z - 071200Z

...DISCUSSION...
Thunderstorm chances will likely be limited on D4/Thursday and
D5/Friday as airmass over the CONUS remains too cold and dry. Some
airmass modification may begin across the southern Plains late
d5/Friday or early D6/Saturday as a shortwave trough progresses
across the western CONUS. As the upper pattern trends more zonal
across the central CONUS, surface lee troughing will sharpen, with
low-level flow forecast to strengthen amid the increasing surface
pressure gradient. The approaching shortwave trough is expected to
continue its eastward progression into the Plains on D6/Saturday and
D7/Sunday, resulting in potential interaction with this return
moisture from central/eastern portions of TX/OK into the Lower MS
Valley. All aspects of the approaching shortwave trough remain
uncertain, with deterministic guidance showing large run-to-run
variability and notable difference between the GEFS and EPS. As
such, overall forecast confidence is low. However, the overall
trends suggests some severe potential may materialize late this
weekend into early next week.

..Mosier.. 12/30/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 310923
SWOD48
SPC AC 310922

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CST Tue Dec 31 2024

Valid 031200Z - 081200Z

...DISCUSSION...
Expansive ridging is forecast to gradually shift from the Plains
into the MS Valley and Southeast on D4/Friday, with stable
conditions prevailing.

A shortwave trough is expected to progress from the western Great
Basin through the Four Corners and into central/southern High Plains
on D5/Saturday, continuing eastward across central/southern Plains
and Mid/Lower MS Valley on D6/Sunday. Surface cyclogenesis appears
probable over the southern High Plains on D5/Saturday ahead of the
approaching shortwave, with a warm sector characterized by mid 60s
dewpoints likely to precede the resulting surface low and attendant
cold front. Thunderstorms are possible from central TX/OK eastward
through the Lower MS Valley on D6/Sunday, as the cold front
interacts with the moderately moist and buoyant air within the warm
sector. Deep-layer vertical shear is expected to be strong enough to
support organized storms (i.e. greater than 40 kt from 0-6 km).

Mid/upper level pattern is similar between the EPS and GEFS, but the
surface pattern has notable differences, with most GEFS members
favoring a slower and more southerly track to the surface low. This
is matched by the deterministic runs of the ECMWF and GFS, while the
Canadian splits the difference. Even though some severe appears
probable, these differences limit the forecast confidence, making it
difficult to ascertain the most likely corridor for severe
thunderstorms. Additionally, all of the deterministic guidance
continues to show notable run-to-run variability. All of these
factors combined with the extended range of the possible severe
(i.e. Day 6) result in too much uncertainty to delineate any risk
areas with this outlook.

The risk for thunderstorms will likely continue along the Gulf Coast
on D7/Monday as this system continues eastward. By D8/Tuesday, cold
and dry conditions are anticipated across the entire CONUS.

..Mosier.. 12/31/2024

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 010940
SWOD48
SPC AC 010939

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CST Wed Jan 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
A shortwave trough is expected to progress from the western Great
Basin through the central Rockies and into central/southern Plains
on D4/Saturday, continuing eastward across the Mid/Lower MS Valley
on D5/Sunday. Surface cyclogenesis is anticipated ahead of this wave
over the southern High Plains on D4/Saturday, with the resulting low
tracking eastward across OK. Strengthening low-level southerly flow
ahead of this low will result in moderate moisture advection, with a
warm sector characterized by 60s dewpoints preceding the low and its
attendant cold front.

Thunderstorms are possible from central TX/OK eastward through the
Lower MS Valley on D5/Sunday, as the cold front interacts with the
moderately moist and buoyant air within the warm sector. Deep-layer
vertical shear is expected to be strong enough to support organized
storms (i.e. greater than 40 kt from 0-6 km). Latest deterministic
runs of the ECMWF and GFS continued to show notable differences,
particularly with the overall speed of the shortwave and its
associated surface low. However, EPS and GEFS members shows greater consistency, with numerous members placing the surface low over the
AR vicinity by D5/Sunday evening. Consequently, there is increased
confidence that the environment over the Lower MS Valley will
support severe thunderstorms D5/Sunday afternoon, with the threat
potentially continuing into the Southeast overnight.

The risk for thunderstorms will likely continue across the Southeast
on D6/Monday as this system continues eastward. Cold and dry
conditions are anticipated across the entire CONUS on D7/Tuesday and D8/Wednesday.

..Mosier.. 01/01/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 020918
SWOD48
SPC AC 020916

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0316 AM CST Thu Jan 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
Medium-range guidance is in relatively good agreement that a
shortwave trough will extend from western/central KS into the TX
Hill Country early D4/Sunday morning. This shortwave is then
forecast to progress northeastward throughout the day, likely
reaching the Mid MS Valley by D5/Monday morning. An associated
surface low will move just ahead of the parent shortwave, with an
attendant cold front sweeping eastward across east TX and Lower MS
Valley. A warm sector characterized by low to mid 60s dewpoints will
precede this front, which should be sufficient for modest buoyancy
despite a relatively warm profile and poor lapse rates.

Thunderstorm development is anticipated along the front, with some
potential for isolated discrete storms ahead of the front as well.
Moderate to strong mid-level flow will extend across the warm
sector, resulting in deep-layer vertical shear strong enough to
support organized storms (i.e. 0-6 km bulk shear from 40 to 50 kt).
General expectation is for the development of a fast-moving
convective line capable of strong to severe gusts along the cold
front, supported by modest buoyancy and deep-layer shear orthogonal
to the front. Strengthening low-level flow (i.e. 50 to 60 kt at 850
mb) could also support enough low-level shear for line-embedded
circulations as well.

Some thunderstorms will remain possible across the Southeast on
D5/Monday as the front continues eastward. However, limited
low-level moisture ahead of the front should limit the severe
thunderstorm threat.

From D6/Tuesday through D8/Thursday, cold and stable conditions are
expected to preclude thunderstorm development across the CONUS.

..Mosier.. 01/02/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 030942
SWOD48
SPC AC 030940

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CST Fri Jan 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
A mid-level trough is forecast to progress eastward into the eastern
U.S. on Monday/Day 4, as an associated cold front moves across the
Atlantic Seaboard. Marginally severe thunderstorms could develop
along or ahead of the front early in the day from Florida northward
into the Carolinas. From Tuesday/Day 5 to Friday/Day 8, cold and dry
high pressure is forecast to settle in across much of the
continental U.S., which is expected to limit thunderstorm potential
in almost all areas.

..Broyles.. 01/03/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 040944
SWOD48
SPC AC 040943

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0343 AM CST Sat Jan 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
A series of upper-level troughs are forecast to move through the
central and eastern U.S. next week, as cold and dry high pressure
dominates over most of the continental U.S. Conditions appear
unfavorable for thunderstorms through Thursday/Day 6. On Friday/Day
7 into Friday night, a large-scale upper-level trough is forecast to
move through the central U.S. At this time, a surface low is
forecast to move from the northern Gulf of Mexico into the
Southeast. Some moisture return will be possible with this system in
the central Gulf Coast states on Friday/Day 7, where isolated
thunderstorms will be possible. A few storms may again develop on
Saturday/Day 8 as the systems affects the Florida Peninsula. No
severe threat is expected in the Day 4 to 8 period.

..Broyles.. 01/04/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 050957
SWOD48
SPC AC 050955

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CST Sun Jan 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
A mid-level trough will move through the eastern U.S. on Wednesday,
as another mid-level trough moves across the Desert Southwest. This
second trough is forecast to move into the Rockies on Thursday/Day 5
and into the Great Plains on Friday/Day 6. Some thunderstorm
activity will be possible across parts of the Texas Coastal Plain
Thursday night, and along the central Gulf Coast on Friday. Ahead of
the system, moisture return is forecast to be minimal across the
western and central Gulf Coast. The airmass overland is expected to
be relatively stable, minimizing any convective potential. As the
mid-level system continues to move eastward, thunderstorms could
develop over parts of Florida on Saturday, with any storms moving
off the coast into the Atlantic on Sunday. Throughout the Day 4 to 8
period, instability is expected to be very limited minimizing any
chance for thunderstorms, and making severe storms very unlikely.

..Broyles.. 01/05/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 060948
SWOD48
SPC AC 060947

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CST Mon Jan 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
At mid-levels, a low is forecast to move into the southern High
Plains on Thursday/Day 4, as southwesterly flow develops over the
south-central U.S. The system will move High Plains on Thursday to
the Southeast by Saturday. Ahead of the associated trough, moisture
return is expected to be limited. This will keep instability mostly
offshore over the Gulf of Mexico. A few thunderstorms could develop
near the western and central Gulf Coast on Thursday and Friday as
the trough passes by. The focus for thunderstorm activity is
forecast to shift eastward into Florida by Saturday. Any severe
threat with this system should be minimal. On Sunday and Monday,
surface high pressure is again forecast to become dominant across
the continental U.S. Cold and dry air will make conditions
unfavorable for thunderstorms.

..Broyles.. 01/06/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 070947
SWOD48
SPC AC 070945

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CST Tue Jan 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
A mid-level trough is forecast to move across the southern Plains on
Friday/Day 4, as flow ahead of the system remains southwesterly over
much of the Southeast. At the surface, a front is forecast to move
into the central Gulf Coast region, with a moist airmass located
ahead of the front mostly offshore. Thunderstorm activity will be
possible from Friday into Saturday along and ahead of the front at
the northern edge of this moist airmass in the coastal sections from
Louisiana to Florida. From Sunday/Day 6 to Tuesday/Day 8,
large-scale mid-level troughing is forecast to persist over the
central U.S. In response, high pressure is forecast to remain
dominant over much of the continental U.S. late in the Day 4 to 8
period. Due to this cold and dry airmass, thunderstorms will be
unlikely.

..Broyles.. 01/07/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 080939
SWOD48
SPC AC 080937

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CST Wed Jan 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
A series of mid-level troughs will move across the continental U.S.
through the middle of next week, as a prevailing northwest flow
pattern continues. In response, a cold and dry airmass will remain
anchored over most of the continental U.S. throughout the Day 4 to 8
period, making thunderstorm development unlikely in most areas.

..Broyles.. 01/08/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 090941
SWOD48
SPC AC 090940

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CST Thu Jan 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
A northwest mid-level flow pattern is forecast to remain in place
over the central U.S. throughout the Day 4 to 8 period, as a series
of shortwave troughs move southeastward through the flow. The
northwesterly flow will help to drive multiple fronts southward into
the central and eastern U.S, which will keep a relatively cold and
dry airmass in place. For this reason, conditions are not expected
to be favorable for thunderstorm development across the continental
U.S. through the middle of next week.

..Broyles.. 01/09/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 100918
SWOD48
SPC AC 100916

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0316 AM CST Fri Jan 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
A broad northwest to westerly mid/upper flow regime will persist
across the CONUS for much of the Day 4-8 period. Strong surface high
pressure also will dominate much of the forecast period, with
continental and offshore low-level trajectories maintaining a dearth
of boundary-layer moisture. Thunderstorm activity is expected to
remain low through the end of the period given a cold, dry, and
stable airmass.

..Leitman.. 01/10/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 110853
SWOD48
SPC AC 110851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 AM CST Sat Jan 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
Strong surface high pressure and a dry/stable airmass will envelop
much of the CONUS through Day 6/Thu. By the end of the period around
Day 7-8/Fri-Sat, medium range guidance indicates a shortwave upper
trough may move across the southern Plains and Southeast. As this
occurs, a deepening surface cyclone will develop over the southern
Plains and shift east. Strengthening southerly low-level flow ahead
of the surface low will allow for Gulf moisture to return northward
across portions of south/east Texas into the Gulf coast states. Some
severe thunderstorm potential could accompany this system at the end
of the forecast period. However, uncertainty and spread in forecast
guidance with regards to timing/track of the surface low, and
moisture return across the Gulf coast region, precludes severe
probabilities at this time.

..Leitman.. 01/11/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 120854
SWOD48
SPC AC 120853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 AM CST Sun Jan 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
Severe thunderstorm potential will remain low Days 4-5/Wed-Thu.
Surface high pressure over the Southeast, and a prior cold frontal
passage deep into the Gulf of Mexico will result in a dearth of
boundary-layer moisture, precluding thunderstorm activity.

Medium range guidance continues to indicate that thunderstorm
potential will increase sometime on Day 6/Fri, and into Days
7-8/Sat-Sun. While details remain uncertain, most guidance depicts
strong deep-layer southwesterly flow spreading from the southern
Plains into the Southeast and Ohio Valley as a series of embedded
shortwave troughs migrate through a broader upper trough across
central and eastern portions of the CONUS. Meanwhile, a surface low
is expected to deepen over the Plains on Day 6/Fri, allowing south/southeasterly low-level flow across the western Gulf to
transport modest moisture northward across the TX vicinity. As the
low progresses east/northeast through the end of the period,
boundary-layer moisture will increase ahead of a cold front across
the Southeast on Day 7/Sat. While surface low and upper trough
track/timing, and quality/extent of northward moisture return remain
uncertain, some increasing severe potential is possible Days
6-7/Fri-Sat across portions of east Texas into the Lower MS
Valley/Gulf Coast vicinity. Outlook probabilities may become
necessary in the next day or two if forecast confidence increases.

..Leitman.. 01/12/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 130859
SWOD48
SPC AC 130858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 AM CST Mon Jan 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
Shortwave upper ridging will move over the southern Plains vicinity
on Day 4/Thu as shortwave trough develops eastward over the
Southwest. While surface lee troughing will develop over the High
Plains as this occurs, high pressure will persist across eastern
portions of the Plains into the Southeast. This will keep Gulf
moisture offshore and thunderstorm potential is low on Day 4/Thu.

Forecast guidance continues to have quite a bit of spread heading
into the weekend (Days 5-6/Fri-Sat). In general, the Southwest upper
trough is expected migrate eastward into the southern Plains on
Friday, and across the Mid-South and Southeast on Saturday. However,
forecast guidance shows a fairly low-amplitude trough despite strong
mid/upper southwesterly flow streaming over the Plains into the
Southeast. A surface low should develop over the southern High
Plains and migrate east through weekend, allowing for northward
transport of Gulf moisture from east TX into the Lower MS Valley and central/eastern Gulf coast vicinity. Guidance varies quite a bit in
the northward extent of moisture return. The ECMWF suite of guidance
is a bit faster and further north compared to the GFS model suite.
Furthermore, SPC and NSSL machine learning guidance has trended
lower with severe potential compared to yesterday. While some severe
potential is possible from east TX into the central Gulf coast
Friday evening into Saturday, confidence remains too low to
delineate unconditional Slight risk probabilities at this time.

By Day 7/Sun, a cold front will move offshore the Atlantic coast and
deep into the Gulf of Mexico. Strong surface high pressure and an
arctic airmass will overspread much of the CONUS, bringing very
cold, dry/stable conditions into early next week.

..Leitman.. 01/13/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 140857
SWOD48
SPC AC 140856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 AM CST Tue Jan 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
Thunderstorm potential will increase on Day 4/Fri into Day 5/Sat
from roughly east Texas into the Lower MS Valley/central Gulf Coast
vicinity. An upper shortwave trough will develop eastward across the
southern Plains and Southeast during this time, before a deeper
large-scale trough quickly follows on its heels. A surface low will
deepen over OK/TX during the day Friday, arriving over the Lower MS
Valley by Day 5/Sat morning. Southerly low-level flow ahead of this
system will allow for northward transport of Gulf moisture across
east TX and the ArkLaTex vicinity. However, 60s F dewpoints are
expected to remain fairly far south across southeast TX into
southern LA through early Saturday. Furthermore, the timing of the
upper trough/surface low coincident with moisture return will occur
overnight. Forecast soundings show strong low-level inhibition, with
only weak elevated instability. While vertical shear will be strong,
supporting some potential storm organization, overall thermodynamic
profiles appear unlikely to support more than isolated strong
storms. Thunderstorm potential could shift east toward the central
Gulf coast on Day 5/Sat, but the upper trough is forecast to weaken
and higher-quality moisture will remain very near the coast. Similar
lackluster thermodynamic profiles as those expected on Day 4/Fri
indicate severe potential will likely remain limited.

Strong surface high pressure and an arctic airmass will settle
across much of the country during the second half of the forecast
period, ending thunderstorm potential through early next week.

..Leitman.. 01/14/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 150903
SWOD48
SPC AC 150901

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0301 AM CST Wed Jan 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
A weak surface low and attendant cold front is forecast to sweep
across the Southeast on Day 4/Sat. Ahead of this feature, low-level
moisture will increase along the central and northeast Gulf coast
vicinity, with 60s F dewpoints generally remaining within the I-10
corridor. More modest moisture is possible across a broader area
from central MS/AL into GA. While mid/upper flow will be quite
strong, thermodynamics will largely limit a greater severe risk.
Nevertheless, isolated thunderstorms, and perhaps a couple of strong
storms, are possible near the immediate Gulf coast. Potential
remains too low however to include 15 percent probabilities at this
time.

By Day 5/Sun, the aforementioned cold front will move offshore.
Strong Arctic high pressure will build southeast and east across
much of the CONUS east of the Rockies through the end of the
forecast period, resulting in a cold, dry, and stable airmass.

..Leitman.. 01/15/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 160906
SWOD48
SPC AC 160905

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0305 AM CST Thu Jan 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
A cold front will move offshore the Atlantic and Gulf coasts on Day
4/Sun. In the wake of the front, strong surface high pressure will
envelop most of the CONUS for much of the forecast period. This
Arctic airmass will bring below normal temperatures for a large part
of the country, resulting in dry/stable conditions and little
potential for thunderstorms.

..Leitman.. 01/16/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 170944
SWOD48
SPC AC 170942

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CST Fri Jan 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
Severe storms are not forecast through the Friday/D8 time frame,
with generally cool and stable conditions persisting.

The large longwave trough will shift east out of the central CONUS
especially on Tuesday D5, while additional waves or amplifications
are expected from the Rockies into the Plains again from Wed/D6 into
Friday/D8. Bouts of high pressure will be maintained over much of
the CONUS as a result of this pattern, with little to no chance of
appreciable low-level moisture return or destabilization over land.

..Jewell.. 01/17/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 180835
SWOD48
SPC AC 180833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0233 AM CST Sat Jan 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
The general pattern of a mid-upper trough over the central/eastern
CONUS will persist through much of the extended outlook period, with
the residual influence of an arctic air mass limiting buoyancy for
the vast majority of the CONUS. There may be some potential for
thunderstorms in the vicinity of south FL by early Wednesday (late
D4 into D5). However, forecast confidence in the sub-synoptic
details is low given a low-amplitude midlevel trough crossing the
northern Gulf of Mexico (with associated timing questions). The
residual arctic air mass and a probable lack of substantial surface cyclogenesis suggest that severe storms are unlikely.

..Thompson.. 01/18/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 190844
SWOD48
SPC AC 190843

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0243 AM CST Sun Jan 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
A relatively stable period will persist through at least Friday/D6
as a large upper trough over the central and eastern CONUS
eventually exits the East Coast around Saturday/D7 morning. Behind
this large-scale feature, zonal flow may briefly develop before
another trough possibly develops to the west. Predictability is very
low for the latter part of the D4-8 period with large model spread,
and as such no severe areas are warranted.

..Jewell.. 01/19/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 200944
SWOD48
SPC AC 200942

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CST Mon Jan 20 2025

Valid 231200Z - 281200Z

...DISCUSSION...
For Thursday/D4 into Friday/D5, a large positive-tilt upper trough
will move from central parts of the CONUS toward the East Coast,
exiting land late Friday. Although strong winds aloft will
overspread the southeastern states, northerly winds are forecast to
hold over land.

Behind that system, high pressure will maintain stable conditions
over the eastern CONUS into Saturday/D6, although more of a zonal
flow regime is forecast thereafter. As a result of this possible
transition to the pattern, minimal low-level moisture return with
low 60s F dewpoints may return to parts of the TX Coast as surface
pressure lowers briefly.

Beyond the D6 time frame, model spread is large, but the general
signal is for the ongoing large trough pattern over the central and
eastern CONUS to at least shift northeastward into eastern Canada
and the northeastern states, allowing for gradual warming across the
South.

..Jewell.. 01/20/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 210904
SWOD48
SPC AC 210902

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0302 AM CST Tue Jan 21 2025

Valid 241200Z - 291200Z

...DISCUSSION...
An amplified and progressive upper trough will move quickly from the
MS Valley to the East Coast on Friday/D4, with zonal flow developing
behind this system. High pressure will follow, maintaining dry
offshore winds across the Southeast.

Models remain in relatively good agreement with the large-scale
pattern through the weekend, depicting a positive-tilt upper trough
over the southwestern states. A broad fetch of west/southwest flow
aloft is forecast to extend across the southern Plains and into much
of the East, with the deep upper low over eastern Canada. Sufficient instability is forecast to develop across parts of southern and
eastern TX into the lower MS Valley Saturday/D5 Night into
Sunday/D6. Given the antecedent cool air at the surface, substantial
clouds and precipitation appear likely, reducing overall
destabilization and severe potential.

Models diverge around Monday/D7, with uncertainly regarding whether
another wave will develop into the northern Plains and Great Lakes
as disturbances rotate around the large-scale low. To the west, the
trough/low over the Southwest may eventually eject east, but timing
for this is uncertain as well with low predictability at this time
frame. In any case, severe potential is forecast to be low through
the period.

..Jewell.. 01/21/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 220732
SWOD48
SPC AC 220730

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0130 AM CST Wed Jan 22 2025

Valid 251200Z - 301200Z

...DISCUSSION...
On Saturday/D4, an upper trough will be exiting the Northeast early,
with temporary zonal flow across much of the central and eastern
states. The large-scale upper low by this time will be located
around Hudson Bay, with a low-amplitude feature possibly rotating
eastward across the Great Lakes. To the west, an upper trough and/or
cut-off low will drift southward across CA and NV, as upper ridging
develops north of there across southern BC and the Pacific NW. High
pressure will remain over the eastern states, providing dry and
stable conditions.

By Sunday/D5, southerly low-level winds across TX and into the lower
MS Valley will allow for at least elevated instability to develop,
and this should favor general thunderstorms from eastern TX to the
MS River. Given the weak instability and likelihood of substantial
clouds and precipitation, severe weather seems unlikely.

This glancing low-level warm/moist advection regime will remain in
place into Monday/D6, with additional precipitation likely across
parts of the Gulf Coast states. Relatively cool boundary-layer
conditions and marginal instability should preclude any severe
changes.

For the Tuesday/D7 time frame and beyond, the upper trough over the
Southwest will eventually proceed east toward the southern Plains,
but predictability is low regarding the timing of this feature.

..Jewell.. 01/22/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 230818
SWOD48
SPC AC 230817

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0217 AM CST Thu Jan 23 2025

Valid 261200Z - 311200Z

...DISCUSSION...
A large upper trough will remain over eastern Canada for much of the
Day 4-8 period, with the southern extent of the colder air aloft
affecting the area from the Great Lakes into the Northeast. Detached
from this feature will be a lower-latitude upper low which is
forecast to drop south across CA on Sunday/D4, and pivot east into
AZ through Monday/D5. For the following days through Thursday/D8,
this low will gradually shift east toward the southern Plains.
However, predictability is low for such a slow-moving feature cut
off from the primary storm track to the north.

Given this pattern, little in the way of a focus will be present for
any severe weather potential until perhaps very late in the period,
Thursday/D8 or beyond. Prior to the southwest-US upper low moving
into the Plains, a general east-west oriented boundary will exist
along the Gulf Coast states, with modest low-level warm advection
resulting in scattered showers and thunderstorms, primarily over
parts of Texas.

..Jewell.. 01/23/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 241001
SWOD48
SPC AC 240959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Fri Jan 24 2025

Valid 271200Z - 011200Z

...DISCUSSION...
On Monday/Day 4, a shortwave ridge is forecast over the
south-central U.S. The overall pattern is forecast to gradually
amplify on Tuesday/Day 5 and Wednesday/Day 6, as a mid-level low
moves slowly eastward across the Desert Southwest. Ahead of the
system, moisture return is expected across the southern Plains in
the early to mid week, as mid-level flow becomes southwesterly. A
moist airmass is forecast to become established across the southern
Plains by Wednesday, with scattered thunderstorms likely to develop
in the afternoon and evening across parts of Texas and Oklahoma. The
potential for convective development is expected to continue into
Thursday/Day 7 and Thursday night as the mid-level system approaches
and moves into the southern Plains. At this time, model forecasts
suggest that instability, lift and deep-layer shear could support an
isolated severe threat in parts of Texas and possibly southern
Oklahoma, from Wednesday evening into Thursday. However, there is
still substantial variance among solutions concerning this system,
and confidence is low concerning magnitude and spacing. At this
time, it appears the overall severe threat will remain marginal. On
Friday/Day 8, the potential for convection is forecast to move
eastward into parts of the Southeast, where little instability is
forecast.

..Broyles.. 01/24/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 250956
SWOD48
SPC AC 250954

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CST Sat Jan 25 2025

Valid 281200Z - 021200Z

...DISCUSSION...
On Tuesday/Day 4, a mid-level low will likely be in the Desert
Southwest. This low is forecast to move southward into northwest
Mexico on Wednesday/Day 5, and then eject eastward across the
southern Plains from Thursday/Day 6 into Friday/Day 7. This system
is forecast to reach the Mississippi Valley late Friday night into
early Saturday/Day 8. Ahead of the system, low-level moisture is
forecast to return northward into parts of southern and central
Texas, where surface dewpoints could reach the 60s F. The models
suggest that destabilization will remain rather weak as the system
approaches Thursday evening. However, strong lift and deep-layer
shear could be enough for organized convection Thursday evening into
Thursday night over parts of south and central Texas. The main
uncertainty is instability, with the models currently having a wide
variance of solutions. The timing of the system is also
questionable, which is forecast to move into the southern Plains
early in the day on Friday. Due to the uncertainties, will not add a
severe threat area at this time.

..Broyles.. 01/25/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 261001
SWOD48
SPC AC 260959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Sun Jan 26 2025

Valid 291200Z - 031200Z

...DISCUSSION...
...Wednesday/Day 4 to Thursday/Day 5...
A mid-level low is forecast to move eastward across the Desert
Southwest from Wednesday/Day 4 into Thursday/Day 5. Low-level
moisture advection will take place ahead of the system across the
southern Plains on Wednesday into Wednesday night, with surface
dewpoints increasing into the 60s F across parts of the southern
Plains. Scattered to numerous thunderstorms appear likely to develop
across the western part of the moist sector Wednesday night across
much of central and northern Texas, as large-scale ascent increases
ahead of the approaching system. This, combined with increasing
instability, and strong deep-layer shear along the western edge of
the moist sector should result in a severe threat late Wednesday
night. A cluster of strong and potentially severe storms may develop
in west-central Texas, with the severe threat persisting into
Thursday, as an MCS moves eastward across the southern Plains.
Supercells with isolated large hail and wind damage will be
possible. There is some concern that moisture return could be slower
than forecast. However, the strength of the system could help to
overcome instability concerns, and it appears a severe threat will
be possible as the mid-level jet ejects northeastward into the
southern Plains from Wednesday night into Thursday.

...Friday/Day 6 and Sunday/Day 8...
The mid-level trough is forecast to move across the southern Plains
on Friday/Day 6, as a cold front advances eastward into the lower
Mississippi Valley. On Saturday/Day 7 and Sunday/Day 8, this front
is forecast to move across the eastern U.S. Although thunderstorms
will be possible along and ahead of the front, instability is
forecast to be very weak suggesting a severe threat will be
unlikely.

..Broyles.. 01/26/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 270954
SWOD48
SPC AC 270953

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Mon Jan 27 2025

Valid 301200Z - 041200Z

...DISCUSSION...
...Thursday/Day 4 and Friday/Day 5...
A mid-level low is forecast to move into the southern High Plains on Thursday/Day 4, as an associated jet streak moves across Texas.
Widespread convection appears likely to be ongoing at the start of
the period, related to an MCS along the western edge of the moist
sector. It appears the MCS will move into central and northeast
Texas during the afternoon, where surface dewpoints should be in the
60s F. This moist and unstable airmass will make strong to severe
thunderstorms be possible in the afternoon as the mid-level jet
ejects northeastward across the region. Supercells with isolated
large hail and severe gusts will be possible.

The mid-level system is forecast to move across the Ark-La-Tex on
Friday/Day 5, as a cold front advances eastward into the central
Gulf Coast states. Thunderstorms will be possible along and ahead of
the front during the day, and a marginal severe threat may develop
near the central Gulf Coast.

...Saturday/Day 6 to Monday/Day 8...
The cold front is forecast to move quickly eastward into the
Atlantic by Saturday as surface high pressure settles over the
eastern U.S. A west-northwest flow mid-level pattern is forecast in
the central and eastern U.S. on Sunday/Day 7 and Monday/Day 8. This
could help to limit moisture return, keeping the chance for
thunderstorms low across the continental U.S.

..Broyles.. 01/27/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 280932
SWOD48
SPC AC 280931

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CST Tue Jan 28 2025

Valid 311200Z - 051200Z

...DISCUSSION...
Models forecast steady eastward progression of a cold front across
the Southeast and Mid-Atlantic region Day 4/Friday, as a mid-level
low devolves into a fast-moving open wave that is expected to cross
the Appalachians Friday night, exiting the East Coast states prior
to the start of the Day 5 period.

While non-zero severe potential will likely exist ahead of the cold
front across southern portions of the central Gulf Coast states, it
appears at this time that instability will remain meager at best,
limiting overall severe potential.

After the front moves offshore, lingering only across the Florida
Peninsula Day 5/Saturday, severe weather is not expected.

Models begin to diverge Day 6/Sunday, with the GFS maintaining a
low-amplitude, quasi-zonal flow regime through much of the remainder
of the period. While the ECMWF undergoes a gradual trend of
slightly greater amplification toward more pronounced eastern U.S.
troughing and central U.S. ridging, prevalence of surface high
pressure/cold continental air east of the Rockies precludes severe
potential through the end of the period.

..Goss.. 01/28/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 290958
SWOD48
SPC AC 290957

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Wed Jan 29 2025

Valid 011200Z - 061200Z

...DISCUSSION...
As a short-wave trough continues shifting away from the U.S./across
the western Atlantic early in the period, flow aloft across the U.S.
is progged by medium-range models to gradually trend toward a more
zonal configuration.

A trough/low is forecast to shift eastward out of the Canadian
Rockies and across the Prairie Provinces days 4-5 (this weekend),
and then eastward across Ontario, Quebec, and eventually the
Maritime Provinces days 5-7 (early next week).

In tandem, an associated/deepening surface low will likewise shift
gradually eastward across southern Canada. As this occurs, an
Arctic cold front will evolve, shifting eastward across the Great
Lakes and then the Northeast, while the trailing portion of the
boundary sags southward in a more west-to-east orientation, roughly
paralleling the zonal flow aloft prevailing by this time over the
CONUS.

With the zonal flow, and sagging west-to-east front, severe-weather
potential appears likely to remain low through the period. While
some convection will be possible near/south of the sagging front,
minimal northward advection of low-level moisture and weak lapse
rates suggest lack of appreciable instability, which it appears at
this time should hinder more robust convection through the period.

..Goss.. 01/29/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 300908
SWOD48
SPC AC 300906

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0306 AM CST Thu Jan 30 2025

Valid 021200Z - 071200Z

...DISCUSSION...
Medium-range models are in reasonably good agreement into Day 6,
with some differences emerging at that point -- and continuing
through the end of the period -- with respect to progression of
small-scale, short-wave troughing moving through the prevailing
westerlies aloft.

During the days 4-5 time frame (Sunday and Monday), upper short-wave
troughing is forecast to move across southern Canada and the Great
Lakes region, and eventually the Ottawa and St. Lawrence Valleys and
into the Canadian Maritimes. As this occurs, and an associated
surface low likewise shifts eastward, a cold front will progress
eastward across the Northeast, while sagging southward across the
central Plains/Midwest. The front will eventually decelerate into
the southern Plains and Southeast states by Day 6 (Tuesday).

Through Day 5, severe weather is not expected. Day 6, potential for
elevated convection -- north of the aforementioned baroclinic zone
-- will become possible, modulated by the passage of disturbances
embedded in the upper westerlies. While models differ on timing and
intensity of these disturbances, it is conceivable that marginal
hail potential could occur at some point through latter stages of
the period. At this time, risk appears low, and too uncertain to
highlight given the subtle/weak nature of the features embedded in
the background low-amplitude flow field.

..Goss.. 01/30/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 311007
SWOD48
SPC AC 311005

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0405 AM CST Fri Jan 31 2025

Valid 031200Z - 081200Z

...DISCUSSION...
A generally low-amplitude upper pattern, characterized by fast
westerly flow aloft, is expected to prevail through the medium-range
period. Global models are in reasonably good agreement with most of
the synoptic-scale details into day 6 (Wednesday), after which
differences become increasingly apparent.

Days 4-5, the generally zonal flow pattern will persist, though some
minor amplification of troughing over the West is expected Day 5, as
the western Canada low drifts southward toward/into the Pacific
Northwest. A rather subtle, lead shortwave trough is forecast to
shift across southern California into the Desert Southwest late day
5 (Tuesday), and into the central Plains through the first half of
day 6. An associated, central Plains surface low is forecast to
evolve, with a cold front shifting out of the southern Rockies
toward the southern Plains. With favorably strong flow aloft, any
elevated destabilization sufficient to support convective
development may result in some potential for hail across central
portions of the country. At this time, however, expectations for
weak instability overall, and likelihood that the boundary layer
remains stable, should preclude appreciable surface based
thunderstorm potential. In any case, any potential for severe
weather appears too low to warrant areal inclusion at this time.

The surface front should continue eastward/southeastward across the
U.S. days 6-7, but even weaker instability expected ahead of the
boundary should preclude any appreciable severe weather potential.

..Goss.. 01/31/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 311011
SWOD48
SPC AC 311009

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0409 AM CST Fri Jan 31 2025

Valid 031200Z - 081200Z

...DISCUSSION...
A generally low-amplitude upper pattern, characterized by fast
westerly flow aloft, is expected to prevail through the medium-range
period. Global models are in reasonably good agreement with most of
the synoptic-scale details into day 6 (Wednesday), after which
differences become increasingly apparent.

Days 4-5, the generally zonal flow pattern will persist, though some
minor amplification of troughing over the West is expected Day 5, as
the western Canada low drifts southward toward/into the Pacific
Northwest. A rather subtle, lead shortwave trough is forecast to
shift across southern California into the Desert Southwest late day
5 (Tuesday), and into the central Plains through the first half of
day 6. An associated, central Plains surface low is forecast to
evolve, with a cold front shifting out of the southern Rockies
toward the southern Plains. With favorably strong flow aloft, any
elevated destabilization sufficient to support convective
development may result in some potential for hail across central
portions of the country. At this time, however, expectations for
weak instability overall, and likelihood that the boundary layer
remains stable, should preclude appreciable surface based
thunderstorm potential. In any case, any potential for severe
weather appears too low to warrant areal inclusion at this time.

The surface front should continue eastward/southeastward across the
U.S. days 6-7, but even weaker instability expected ahead of the
boundary should preclude any appreciable severe weather potential.

..Goss.. 01/31/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 011001
SWOD48
SPC AC 010959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Sat Feb 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
Medium-range models continue to depict generally zonal flow across
the U.S. through the medium-range period. By the start of the
period, a prominent baroclinic zone at the leading edge of an Arctic
airmass is progged to have become established in a roughly
west-to-east manner from the Mid-Atlantic region west-southwestward
into the southern Plains. Weak/subtle perturbations forecast to
move across the U.S. within the background/fast westerly flow regime
are expected to modulate the north-south position of this boundary,
but with its average location remaining roughly unchanged through
day 6 -- after which evolving model differences cast more
substantial uncertainty into the forecast.

At this time, it appears that mainly elevated convection -- and
perhaps a limited potential for hail -- may evolve primarily north
of the front, in the late day 4 to early day 6 time frame, from the
central U.S. eastward into the Tennessee Valley/Mid South region.
However, at this time, risk appears to limited/low to highlight with
a 15% probability area.

..Goss.. 02/01/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 020953
SWOD48
SPC AC 020951

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CST Sun Feb 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
Uncertainty remains high in the medium-range period, in terms of
both pattern evolution, and attendant potential for severe weather.
Models agree in general that early in the period, a quasi-zonal
pattern aloft will prevail across the U.S., and a roughly
west-to-east surface baroclinic zone will be in place from the
central/southern Plains vicinity eastward to the Carolinas.

Initially, any convective potential should remain limited, and
largely confined to the cool side of the surface front. However,
emerging model differences become evident, even early in the period,
in terms of the eastward advance of various short-wave disturbances
through the background westerlies. This progression of short-wave
energy -- varying in degree from model to model -- results in
correspondingly varying degrees of amplification of the flow field
aloft, and also correspondingly, varying levels of mass response at
the surface.

Within the generally more amplified ECMWF, even early in the period
but particularly through the middle and later stages of the
forecast, likelihood for greater northward transport of higher
theta-e air would exist, meaning greater potential for
destabilization, and -- given flow aloft more than sufficient for
organized convection -- greater potential for severe weather.

With all of that said, given what appears to be a pattern of
inherently low predictability, delineating areas of severe-weather
potential would appear imprudent at this time, at the medium-range
time frames.

..Goss.. 02/02/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 031004
SWOD48
SPC AC 031003

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0403 AM CST Mon Feb 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
A short-wave trough is progged to be moving across the Midwest/Ohio
Valley day 4 (Thursday), along with a weak surface wave moving along
a baroclinic zone separating Arctic air to the north, and a more temperate/modifying continental airmass to the south. Late day 4
(Friday morning), the low is forecast to undergo significant
cyclogenesis over the Canadian Maritimes, with the trailing surface
front becoming realigned in an east/west orientation from the
Carolinas to the southern Plains.

During the day 4 period, as the cold front progresses southward
across the Mid South in the immediate wake of the weak frontal wave,
showers and isolated thunderstorms -- initially confined to the cool
side of the front -- will likely develop across the Mid South in a
weakly destabilizing warm sector. With strong/weakly veering flow
through the lower troposphere, storms which do develop would be
fast-moving, and could intensify locally to near severe levels.
However, current expectations are that the degree of surface-based destabilization will be limited, and thus overall severe potential
tempered as well. While low-probability severe risk across parts of
the Mid South may be required in later outlooks, the risk appears
too low to highlight at this time.

Day 5, the next short-wave trough is forecast to be crossing the
Rockies, and will likely begin impinging on the Plains overnight.
This will support new frontal low development along the pre-existing west-to-east baroclinic zone. At this time, projections are that a
developing low may exist over the Ozarks vicinity, but with limited
CAPE expected in the evolving warm sector, severe weather potential
would appear minimal at best.

Day 6, the low is forecast to move rapidly east-northeastward across
the Ohio Valley through the day, and then on into/across New England
overnight. As this occurs, the trailing portion of the baroclinic
zone should surge southeastward with time -- reaching a position
from the Mid-Atlantic region to the Gulf Coast States late. Once
again, showers and a few thunderstorms will likely occur within the
warm sector, but again, limited CAPE should continue to characterize
the pre-frontal environment, tempering overall risk for severe
weather.

The front should be continuing southward Day 7, moving off the Gulf
Coast during the period. Limited CAPE and weaker flow with
southward extent should continue to limit any severe risk,
continuing through day 8 as the front shifts across Florida through
the end of the period.

..Goss.. 02/03/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 041001
SWOD48
SPC AC 040959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Tue Feb 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
Medium-range models are in reasonably good agreement through day 6
(Sunday), in terms of large-scale features. Substantial divergence
begins thereafter, casting substantial uncertainty into the forecast
beyond the upcoming weekend.

Day 4, as an upper short-wave trough crossing the Northeast moves
into/across the Canadian Maritimes, the quasi-zonal flow pattern
over the U.S. will continue. Weak amplification of the flow will
occur over the West with time, however, as a short-wave trough moves
across the Rockies. As this occurs, frontal low development is
expected along the persistent west-to-east front lying from the
southern Plains to the Mid-Atlantic region. However, with only weak instability expected near the developing low, and eastward along the
front, convection is forecast to remain disorganized.

Day 5, the upper wave is forecast to continue eastward across the
central and northern Plains through the day, and into and across the
Great Lakes region overnight. The associated frontal low --
initially progged to lie over the Oklahoma vicinity, will deepen as
it shifts east-northeastward with time, reaching the northeast
through the end of the period. The trailing surface front will
sharpen and advance southeastward, extending from the Mid-Atlantic
region southwestward to coastal Texas late. While showers and a few thunderstorms will be associated with the frontal advance, weak
instability anticipated at this time should again hinder convective
intensity.

Day 6, as the low moves offshore and the front continues advancing
steadily southeastward, it should clear the Atlantic and Gulf Coasts
during the evening, lingering only across Florida through the end of
the period. The continued trend of weak instability, as well as
weakening flow with southward extent, should hinder prospects for
more robust convection.

..Goss.. 02/04/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 050937
SWOD48
SPC AC 050936

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0336 AM CST Wed Feb 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
Medium-range global models appear to be in reasonable large-scale
agreement into the first half of day 6 (Monday). At this point,
more substantial differences begin to emerge with respect to the
amplification of the flow field across the U.S., as the main western
U.S. trough begins a slow eastward advance. These differences are
significant in that speed and timing of the advance of this system
will influence surface cyclogenesis along what has been a
persistent, roughly west-to-east baroclinic zone across the
south-central and southeastern CONUS. Stronger/inland low
development along this front would potential bring an increase in severe-weather potential, but this scenario is far too uncertain at
this point to highlight through the second half of the period.

Earlier in the period, a frontal low along the surface baroclinic
zone is forecast to shift out of the Oklahoma vicinity, and
east-northeastward across the Ohio Valley area day 4, before
reaching the southern New England coastal vicinity by the start of
day 5. However, very weak warm-sector instability is expected at
this time, which should preclude severe risk. As the low deepens
northward into the Canadian Maritimes, the trailing cold front
should settle back into its recently persistent position from the
southern Plains to the Southeast, and remain there into the Day 6
period ahead of the advancing western upper trough. Again, with
weak instability near the boundary and southward into the warm
sector, severe weather is not expected.

..Goss.. 02/05/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 060957
SWOD48
SPC AC 060956

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CST Thu Feb 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
The zonal flow aloft which has persisted over the U.S. recently --
and into the start of the medium-range period -- is progged to
gradually amplify, with flow becoming more cyclonic with time across
the U.S. through the period. The initial effect of this gradual
upper flow field evolution will be to gradually suppress the
persistent west-to-east surface front over the U.S. southward.
Through day 5 (Monday), this front should extend from Texas eastward
through the Gulf Coast States to Georgia/South Carolina. Severe
weather is not expected, as this front drifts southward and settles
across this area.

Through the second half of the period (late day 6 onward),
disturbances moving across the southern U.S. within increasingly
cyclonic flow aloft will influence potential for surface wave
development along the front. Any appreciable cyclogenesis could
result in northward transport of higher theta-e Gulf air, and thus
some destabilization ahead of the low. With strong flow aloft atop
the surface front, this would suggest an environment that would
support severe-weather potential.

With that said, while a general/overall increase in severe-weather probabilities over the Gulf Coast region is becoming evident during
the second half of the period, uncertainty remains high. Timing and
degree of any such risk will depend upon subtle features aloft, and
their effects on surface mass response. And given predictability
issues with respect to timing an intensity of such subtle features,
it appears premature at this time to introduce 15% risk areas in the
day 7 to 8 time frame.

..Goss.. 02/06/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 070949
SWOD48
SPC AC 070947

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CST Fri Feb 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
Fairly zonal flow across the CONUS will evolve into broadly cyclonic
flow as a western trough begins to amplify by the middle of next
week. This trough will be the focus of severe weather potential from
the Sabine Valley into the central Gulf Coast region by late in the
week. Another western trough is forecast by late next week.
Uncertainty in the timing and evolution of these features is high,
however.

...Central Gulf Coast Vicinity...
Model variability remains rather high for the Tuesday through
Thursday period. While there is general consensus between the
GFS/ECMWF that a western upper trough will be amplifying, the
shortwave trough that ultimately ejects into the southern Plains is
out of phase between the two models--the ECMWF being the more progressive/intense of the two. These differences lead to timing and
magnitude variability of the surface low and northward advancement
of Gulf moisture. Pattern-wise, upper 60s to low 70s F dewpoints
currently reside in the Gulf and the upcoming cold front this
Sunday/Monday is not expected to push that moisture south. Some
increase in severe potential would be expected as the upper trough
approaches. At present, model and ML guidance would suggest the
greatest severe potential would exist on Wednesday or Thursday
depending on the timing/evolution of the upper wave. Confidence
remains too low for severe probabilities, but model trends will
continue to be monitored.

By next Friday, models are currently in agreement that another
western trough will amplify. Even with this consistency, the frontal
intrusion into the Gulf prior to this secondary trough casts doubt
on the quality of moisture return this far in advance. Uncertainty
is too high for highlights.

..Wendt.. 02/07/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 080948
SWOD48
SPC AC 080946

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0346 AM CST Sat Feb 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
Severe weather potential is expected to increase by the middle of
next week. As the upper trough ejects into the southern/central
Plains, moisture that is expected to remain just off the Gulf coast
will advect northward Tuesday/Wednesday. At least isolated severe
storms could occur from the Sabine Valley into portions of the Lower Mississippi Valley on Wednesday. Early-day precipitation, stronger
forcing displaced to the north, and upper-level winds roughly
parallel to the surface boundary reduce confidence in more
widespread severe storms. On Thursday, the front will push into the
Southeast. Upper-level flow will remain strong over the region, but
the mid-level ascent and surface cyclone will move farther north and
the warm sector will likely be narrow.

By late next week, the cold front is forecast to stall near the Gulf
Coast. Another slightly more amplified upper trough will move
eastward into the weekend. Depending on the degree of cold air
intrusion into the Gulf Thursday/Friday and the strength of the
trough/surface cyclone, more robust moisture return will be possible
during the weekend. Uncertainty remains high at this juncture as
models have not been overly consistent with this signal in the past
1-2 days of runs. Trends will continue to be monitored.

..Wendt.. 02/08/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 090956
SWOD48
SPC AC 090954

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CST Sun Feb 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
...Sabine Valley into Lower Mississippi Valley Vicinity...
Precipitation appears likely to be ongoing within the warm advection
zone near the cold front on Wednesday. The primary shortwave
perturbation within the broader cyclonic flow aloft is expected to
move from the southern Plains into the mid-Mississippi Valley by the
afternoon. A weak surface wave will develop along the front and
quickly move northeast. This overall pattern will not favor
significant northward progression of Gulf moisture. With deep-layer
shear remaining parallel to the boundary, a broad warm advection
regime, and stronger ascent displaced northward, confidence in more
than isolated disorganized severe storms is low.

The intrusion of cold air into the Gulf on Friday is expected to be
greater than earlier in the week. Portions of the northern Gulf are
likely to be impacted with some potential the cold air to reach the
central Gulf. By Friday afternoon, the next upper-level trough is
forecast to reach the Southwest with a lee cyclone developing in
eastern Colorado. With the low deepening as it moves into the
Mid-South, rapid northward moisture return is possible within the
region through the day Saturday. This pattern would support severe
storms. Model guidance has had some consistency with the broad
pattern evolution, but has continued to differ run to run with
timing and intensity of key features. Further, given the colder air
that will be in place prior to any moisture return, the overall
quality of the airmass ahead of the upper trough is also not
certain. Trends in guidance will continue to be monitored for this
coming Saturday.

...Portions of the Southeast...
As the surface low moves northeast, it is expected to deepen as it
moves into the southern/central Appalachians on Thursday. This will
push the cold front into Georgia and the Carolinas. A narrow
warm-sector ahead of the front may destabilize enough for isolated
strong to severe storms, but confidence in more widespread activity
is low given the uncertain buoyancy and the increasingly
northward-displace mid-level ascent.

On Sunday, based on current guidance, a similar scenario to Thursday
will occur. However, the trough/surface low are forecast to be
stronger and there is greater potential for a larger warm sector.
Uncertainty remains high this far in advance, however.

..Wendt.. 02/09/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 100939
SWOD48
SPC AC 100937

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CST Mon Feb 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
There appears to be severe potential along parts of the East Coast
as the initial trough moves offshore on Thursday. In advance of the
next trough, initial moisture return into the lower Mississippi
Valley region could promote some severe potential late Friday.
Uncertainty in the environment/forcing precludes highlights both
days. Severe weather potential increases further on Saturday in the
Southeast and may linger into Sunday along the East Coast. For
Monday, broad surface high pressure and cold air east of the Divide
will minimize severe risk.

...Southeast...
There has been a consistent signal for a potent upper-level trough
to move into the West Coast on Friday. In response to this trough, a
deep surface low is expected to develop in eastern Colorado and move
into Oklahoma. These features will promote strong moisture return
into parts of the central Gulf Coast states late Friday into
Saturday. Appreciable moisture return may reach into the Mid-South.
This setup would favor scattered to numerous severe storms from the
Sabine Valley vicinity into much of Mississippi/Alabama. Both
low-level and deep-layer shear would be strong in this regime. The
surging cold front will likely be the primary focus for storms, but
the strong synoptic forcing within a potentially weakly capped
boundary-layer could also bring about more discrete storms ahead of
the line as well. The primary uncertainties will be the
timing/amplitude of the trough as well northward/eastward extent of
sufficient buoyancy. With the consistent signal in deterministic and
ML guidance, 15% severe probabilities appear warranted for Saturday.
Refinement of the highlighted area is probable as additional data
becomes available.

...Carolinas into Mid-Atlantic...
As the strong trough, surface low, and cold front continue east on
Sunday, there will be some potential for additional severe storms
from the Mid-Atlantic in to portions of the Carolinas. It is not
clear if the timing of these features will be well phased with the
diurnal cycle. Trends in guidance will continue to be monitored.

..Wendt.. 02/10/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 110939
SWOD48
SPC AC 110938

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CST Tue Feb 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
...Day 4/Friday...
Late in the period, the approaching trough will promote moisture
return within the Lower Mississippi Valley, Arkansas, and East
Texas. Model guidance shows some hints at potential storm
development, but coverage is far from certain due to some lingering
capping from warmer air aloft. Should storms form, they most likely
would be elevated. Coverage concerns preclude adding severe
probabilities, but large hail is conditionally possible.

...Day 5/Saturday...
A strong trough, which has trended more amplified in the ECMWF, is
expected to impact the Sabine Valley into the Southeast starting in
the afternoon. The latest model trends also have a more favorable
placement of the surface low in the Tennessee Valley. These factors
will drive strong moisture advection into the region by Saturday
morning, continuing into Sunday. Intense wind fields throughout the
column will support organized storms capable of all hazards.
Damaging winds, particularly with linear convection along the strong
cold front, currently appears as the main threat. The magnitude of
the tornado threat will largely depend on discrete development ahead
of the front. Given the moist environment with minimal inhibition
and strong forcing, that scenario is certainly plausible. Discrete
development or not, low-level wind fields still will support
line-embedded circulations. Despite more limited buoyancy farther
north, the strongly forced convective line and 60-70 kts of 850 mb
flow would support damaging winds even in shallow convection.
Uncertainties still remain along the fringes of the highlighted area
(i.e., how far west will convection form, how unstable will it be to
the north/east). Mid-level lapse rates will also not be overlay
steep. Even so, the overall pattern continues to support the
potential for scattered to numerous severe storms.

...Day 6/Sunday...
As the strong trough and cold front continue east, the convective
line will likely stretch from the eastern Florida Panhandle into the
Piedmont early Sunday morning. Strong forcing and wind fields will
still be in place. The primary uncertainty is the degree of
destabilization that can occur ahead of the line given the arrival
before the diurnal heating maximum. Where heating can occur, which
may be near the coastline, some severe potential will exist. The
intensity and coverage of these storms is enough in question that
severe probabilities will be withheld.

...Day 7 Onward...
Severe potential should be minimal on Monday given the expansive
colder air and surface high pressure. Another shortwave trough will
approach the southern Plains on Tuesday. While some moisture return
is possible, this will occur after a fairly substantial cold air
intrusion to the central Gulf. Uncertainty in an appreciable severe
risk is high.

..Wendt.. 02/11/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 121000
SWOD48
SPC AC 120959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Wed Feb 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
...Day 4/Saturday...
Model guidance continues to forecast a strong upper-level trough
moving through the southern Plains and into the Southeast. Some
modest slowing of the trough has been noted, however. The trough
will promote the deepening of the surface low in the ArkLaTex
vicinity during the afternoon with further deepening expected into
the evening as it generally progresses north-northeastward within
the Mid-South/Ohio Valley. Moisture return will have begun Friday
evening and will continue Saturday. Guidance shows a consistent
signal for mid 60s F dewpoints extending into much of
Louisiana/Mississippi, and Alabama. Upper 60s F dewpoints are
possible closer to the Gulf Coast. Very strong wind fields are
anticipated throughout the troposphere. Shear will be strong and,
despite more modest mid-level lapse rates, buoyancy will be more
than adequate for severe storms. The current expectation is for warm
advection precipitation to be ongoing early in the period and for it
not to make much, if any, southward progress until the late
afternoon. A Pacific front in East Texas/Sabine Valley into the
ArkLaTex may be the initial zone for stronger convective
development. By the late afternoon onward, the cold front will begin
to surge south and east. The low-level jet should remain strong into
the afternoon and then increase to 50-70 kts during the evening. As
the cold front surges, shear vectors will acquire a greater
cross-boundary component. This strongly forced line will be capable
of scattered to widespread damaging winds along with the threat for
embedded circulations/QLCS tornadoes. One of the main questions that
remain will be the degree of the tornado threat, which would
increase with any discrete activity ahead of the cold front. Given
the weak capping and strong forcing, pre-frontal discrete storms are
plausible. The ECMWF shows some hint of this from central Louisiana
into adjacent Mississippi. The eastern and northern extent of the
greatest severe threat are also in question, but the intense
low-level jet could produce severe-caliber gusts even with
relatively shallow convection. The overall pattern, along with
signals in both deterministic and ML guidance, suggest 30% severe
probabilities are warranted for Saturday.

...Day 5/Sunday...
The strongly forced line will continue into portions of the
Carolinas and Mid-Atlantic. Strong wind-fields will remain in place.
The main question will be the degree of destabilization that can
occur. The current forecast guidance suggests the line may move
through these areas late morning/early afternoon. Uncertainty in the thermodynamic environment precludes severe probabilities at this
time, but areas of eastern Virginia into parts of the eastern
Carolinas will continue to be monitored.

...Day 6/Monday Onward...
With cold air moving into much of the CONUS east of the Divide,
severe potential appears low during the remainder of the period.
Some moisture return could occur in coastal Texas next Tuesday, but
a cold front is expected to quickly push back offshore.

..Wendt.. 02/12/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 130938
SWOD48
SPC AC 130937

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CST Thu Feb 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
...Day 4/Sunday...Eastern Virginia/North Carolina...
Strong mid-level ascent and a surface low moving through the
Mid-Atlantic will bring strong wind fields to eastern Virginia an
eastern North Carolina. While the surface cold front is not expected
to move through these areas until mid/late morning, it is not clear
how much destabilization will occur prior to its passage. Available
forecast soundings suggest ample mid/upper-level cloud cover and
subsequently cooler surface temperatures. Still, some moisture
return ahead of the front may support at least shallow convection.
Given the strong wind fields, some damaging winds could occur. Given
the uncertainties, severe probabilities will be withheld.

Beyond Sunday, expansive surface high pressure and cold air are
generally expected across much of the CONUS. Severe potential
through the middle of next week appears quite low. Models do hint at
a surface cyclone developing along a cold front in the northern Gulf
mid to late next week, but severe potential with that feature is far
too uncertain this far in advance.

..Wendt.. 02/13/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 140852
SWOD48
SPC AC 140851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 AM CST Fri Feb 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
Strong surface high pressure is forecast to extend from the northern Rockies/Plains through much of the Midwest on Day 4/Mon. A prior
cold frontal passage into the Atlantic and Gulf waters will leave a
dearth of boundary-layer moisture east of the Rockies. An upper
trough will deepen on Day 5/Tue, moving from the Southwest and Great
Basin to the Atlantic coast by Day 8/Fri. A weak surface low may
develop across Texas on Day 5/Tue ahead of the upper trough,
allowing some moisture return across southeast TX. Some thunderstorm
activity is possible ahead of a strong Arctic cold front, but severe
potential appears limited. The Arctic front will continue to
progress eastward, moving offshore the Gulf coast by Day 7/Thu
morning. A very cold and dry airmass in the wake of this system will
preclude thunderstorm potential across the CONUS late in the
forecast period.

..Leitman.. 02/14/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 150931
SWOD48
SPC AC 150930

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CST Sat Feb 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
An Arctic cold front is expected to surge south and east across the
southern Plains and Lower MS Valley on Day 4/Tue. Some thunderstorm
potential is possible across the TX Coastal Plain ahead of the front
as southerly low-level flow allows northward transport of Gulf
moisture. Some potential for an isolated strong to severe
thunderstorm will exist across southeast TX during the late
afternoon/evening. However, current forecast guidance suggests
convection may be elevated due to poor low-level lapse rates and
convection becoming quickly undercut by the surging front.
Currently, the overall threat appears limited in space and time,
though some low-end probabilities may be needed in subsequent
outlooks.

An Arctic airmass will settle over much of the CONUS on Day 5/Wed,
resulting in very cold and stable conditions through the end of the
period. This will preclude thunderstorm potential beyond Day 4/Tue.

..Leitman.. 02/15/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 160902
SWOD48
SPC AC 160900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 AM CST Sun Feb 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
A shortwave trough embedded within a larger-scale upper trough over
the eastern U.S. will move across the Southeast on Day 4/Wed. At the
surface, a cold front will sweep across the central Gulf coast, GA
and FL. Thunderstorms will likely accompany the front, with some
potential for isolated strong storms across north FL, though overall
severe potential appears too limited to include probabilities at
this time.

After Day 4/Wed, strong surface high pressure and cold/stable
conditions will prevail the remainder of the forecast period. Little thunderstorm potential is expected Day 5/Thu through the weekend.

..Leitman.. 02/16/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 170857
SWOD48
SPC AC 170856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 AM CST Mon Feb 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
In the wake of a prior Arctic cold front moving offshore the Gulf
and Atlantic coasts, strong surface high pressure will settle over a
large portion of the CONUS through much of the period. This will
result in a dry, stable airmass and thunderstorm potential will be
low. Severe storms are not expected during the Day 4-8 period.

..Leitman.. 02/17/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 180917
SWOD48
SPC AC 180915

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0315 AM CST Tue Feb 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
Dry and stable surface high pressure will persist across much of the
CONUS during the Day 4-8 period. This will result in a dearth of
moisture and continental trajectories preclude Gulf moisture return.
By the end of the period around Day 8/Tue, an upper ridge over the
western U.S. will creep east over the Plains. This may allow some
modest Gulf moisture to return northward across parts of TX.
Regardless, thunderstorm potential appears low this weekend into
early next week.

..Leitman.. 02/18/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 190854
SWOD48
SPC AC 190852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 AM CST Wed Feb 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
Persistent surface high pressure across portions of the Southeast
and Gulf Coast regions will result in a dearth of boundary layer
moisture through at least Day 6/Mon. This will preclude much
potential for thunderstorms.

By the end of the period, around Days 7-8/Tue-Wed, an upper ridge
over the western U.S. will weaken as it shifts east toward the
Plains, owing to an upper shortwave trough developing southeast
across the Rockies. This will result in lee low development across
the southern Plains. Forecast guidance is in fairly good agreement
even at this extended range that a surface low will move from the
southern Plains to the Mid-South vicinity. In response, southerly
low-level flow across the western Gulf will transport modest
moisture northward ahead of a cold front from the ArkLaTex into the
Deep South by Day 8/Wed. While severe potential appears limited by
weak moisture return, thunderstorm potential is likely to increase
late Day 7/Tue into Day 8/Wed.

..Leitman.. 02/19/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 200951
SWOD48
SPC AC 200950

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CST Thu Feb 20 2025

Valid 231200Z - 281200Z

...DISCUSSION...
Isolated showers and thunderstorms may occur over parts of the
western to central Gulf coast vicinity on Day 4/Sun in association
with a weakening upper shortwave trough moving across the region.

After a lull in precipitation potential around Days 5-6/Mon-Tue,
thunderstorm potential may increase late in the forecast period. An
upper ridge over the western U.S. will shift east across the Plains
on Day 7/Wed before a deepening trough ejects across the Rockies to
the MS Valley on Day 8/Thu. During this time, lee low development
over the southern Plains will result in strengthening southerly
low-level flow over the western Gulf. Increasing moisture return
ahead of the eastward developing low and attendant cold front will
likely result in thunderstorm development from the ArkLaTex to the
Mid-South vicinity on Day 8/Thu. While some severe potential could
become favorable in this pattern, uncertainty regarding northward
extent of moisture return, and timing of key features at this longer
time range, precludes severe probabilities at this time.

..Leitman.. 02/20/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 210922
SWOD48
SPC AC 210921

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0321 AM CST Fri Feb 21 2025

Valid 241200Z - 011200Z

...DISCUSSION...
A dry airmass will be in place across the CONUS for all of next
week. A cold front will move south across the Gulf on Monday. While
some moisture recovery will occur on Tuesday and Wednesday, another
front will move into the northern Gulf on Wednesday night and keep
moisture offshore. Therefore, thunderstorm activity should be
minimal and severe thunderstorms remain unlikely through the
extended forecast period.

..Bentley.. 02/21/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 220853
SWOD48
SPC AC 220852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 AM CST Sat Feb 22 2025

Valid 251200Z - 021200Z

...DISCUSSION...
At the beginning of the forecast period, dry conditions will be
prevalent across the entire Gulf basin. Southerly flow and some
moisture return will begin Tuesday and Wednesday before another cold
front pushes dry air into the Gulf again early Thursday. This
continued dry air across the Gulf will continue to limit moisture
availability needed for any severe weather threat. Beyond D8/Sat
there is a better signal for ridging across the central Plains and a
return to quality low-level moisture across parts of Texas. However,
until that time, severe weather potential will remain low.

..Bentley.. 02/22/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 230935
SWOD48
SPC AC 230933

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CST Sun Feb 23 2025

Valid 261200Z - 031200Z

...DISCUSSION...
Moisture will start to advance inland across Texas on Wednesday/D4,
but will be shunted into the Gulf on Thursday as a cold front
advances south. This will result in minimal thunderstorm activity
for much of the extended forecast period. By Sunday/D8 and beyond,
most extended range forecast guidance suggests significant moisture
recovery across the Gulf and some inland moisture intrusion across
the Southern Plains and Southeast which will likely increase
thunderstorm and severe weather potential. However, until that time, thunderstorm and severe weather potential remains low due to the
lack of sufficient instability.

..Bentley.. 02/23/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 240956
SWOD48
SPC AC 240954

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CST Mon Feb 24 2025

Valid 271200Z - 041200Z

...DISCUSSION...
A strong mid-level trough will amplify across the East Coast on
Thursday with a strong cold front sharpening along the Appalachians
and moving into the Atlantic. Given the persistent continental
airmass preceding the cold front with minimal moisture recovery,
instablity should be quite weak. However, forecast soundings show
some weak instability which could promote a few lightning flashes
across the Carolinas and vicinity.

In the wake of the cold front, dry air will remain across the CONUS
and will penetrate well into the Gulf. This should limit any
lightning potential on Friday and Saturday. By D7/Sun an D8/Mon,
sufficient moisture recovery across the Gulf and inland penetration
across the southern Plains and Southeast may result in the potential
for thunderstorms and perhaps a few strong to severe storms.
However, at this time, this potential does not appear high enough to
warrant severe weather probabilities for either day.

..Bentley.. 02/24/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 250957
SWOD48
SPC AC 250955

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CST Tue Feb 25 2025

Valid 281200Z - 051200Z

...DISCUSSION...
A dry, continental airmass across the eastern CONUS and northern
Gulf will keep severe weather potential low on D4/Fri and D5/Sat. By
D6/Sun, as the mid-level low starts to translate into the southern
Plains, robust low-level moisture advection is expected to occur
ahead of a developing surface cyclone. After this time, severe
weather may be possible any day through early next week. In general,
the overall pattern suggests moisture returning to the southern
Plains and parts of the Southeast with a broad trough in the western
CONUS with a series of shortwave troughs advecting into the Plains
and eventually across the eastern CONUS. This pattern will likely
support one or more severe weather episodes, but pinpointing the
exact day and location will require less variance in the timing and
amplitude of the mid-level pattern within the extended range
ensemble suite. Therefore, no severe weather probabilities are
warranted at this time.

..Bentley.. 02/25/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 260955
SWOD48
SPC AC 260954

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CST Wed Feb 26 2025

Valid 011200Z - 061200Z

...DISCUSSION...
Severe weather potential will be low to start the period with
northerly flow across the Gulf on D4/Saturday. On D5/Sunday, a
compact mid-level low will translate east across the Southwest which
will result in lee cyclogenesis in the southern/central High Plains.
As surface high pressure across the Midwest translates east,
favorable low-level trajectories and strengthening flow across the
Gulf and southern Plains will initiate significant moisture return
across Texas. The initial mid-level low will weaken as it moves
across the Plains and into the Mid-Mississippi Valley on D6/Monday.
However, lee cyclogenesis will likely strengthen Monday afternoon as
a larger scale trough approaches the southern Plains. Shortwave
ridging will likely keep the dryline capped on Monday with continued
moistening beneath the capping inversion as low-level moisture
advection continues.

...D7/Tue - East Texas into the Mid/Lower Mississippi Valley...
By 12Z Tuesday, moisture recovery across the western Gulf should be
complete with 70F dewpoints forecast by both GFS and ECMWF
ensembles. Aloft however, there is significant disagreement
regarding the amplitude of the larger scale wave on Tuesday. The
less amplified GFS seems to be the outlier, with a more amplified
solution preferred by most other extended range guidance. However,
even the GFS would pose a severe weather threat across parts of East
Texas into the Mid-Lower Mississippi Valley. The inherent
uncertainty in a Day 7 forecast and the modest spread regarding the
mid-level trough evolution make specific factors such as severe
hazards and storm mode nebulous at this time. However, there is
enough confidence in at least mid-60s dewpoints well inland with an
ejecting large scale trough, to introduce broad 15% severe weather probabilities on D7/Tuesday from East Texas to the Mid-Mississippi
Valley region.

...D8/Wed - Carolinas into the Southeast...
Some severe weather threat will likely exist on Wednesday ahead of a
squall line that may be ongoing along or ahead of the cold front.
Uncertainties in the mid-level pattern on Tue/D7 will be further
exacerbated on Day 8. In addition, it is unclear whether full
moisture recovery will occur across the eastern Gulf ahead of the
cold frontal passage. This will have significant implications on the
moisture quality ahead of the front on Wed/D8 and thus the
instability available.

..Bentley.. 02/26/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 271003
SWOD48
SPC AC 271002

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0402 AM CST Thu Feb 27 2025

Valid 021200Z - 071200Z

...DISCUSSION...
...D6/Tue - East Texas into the Mid/Lower Mississippi Valley...
A compact mid-level low will translate east across the Southwest on
Sunday which will result in lee cyclogenesis in the southern/central
High Plains. As surface high pressure across the Midwest translates
east, favorable low-level trajectories and strengthening flow across
the Gulf and southern Plains will initiate significant moisture
return across Texas. The initial mid-level low will weaken as it
moves across the Plains and into the Mid-Mississippi Valley on
D5/Monday. However, lee cyclogenesis will likely strengthen Monday
afternoon as a larger scale trough approaches the southern Plains.
Shortwave ridging will likely keep the dryline capped on Monday with
continued moistening beneath the capping inversion as low-level
moisture advection continues.

By 12Z Tuesday, moisture recovery across the western Gulf should be
complete with 70F dewpoints forecast near the Gulf Coast by both GFS
and ECMWF ensembles. Confidence in the upper-level pattern is
increasing as the ECMWF and EC Ensembles have been consistent with
an amplified mid-level pattern across the central and southern
Plains now for several consecutive runs. In addition, the GFS/GEFS
has trended toward the more amplified ECMWF solution. As the
confidence in the overall pattern increases, the confidence for a
significant severe weather threat has also increased and 30% severe
weather probabilities have been added from East Texas to central
Mississippi. While specifics will remain uncertain until the event
draws closer, the potential for multiple rounds of severe convection
including supercells, clusters, and likely an eventual squall line
will likely bring a threat for all severe weather hazards including
strong tornadoes.

...D7/Wed - Carolinas into the Southeast...
The ECMWF/ECS, which has been several days ahead of other extended
guidance on with this upcoming pattern, has trended toward greater
moisture penetration into the Southeast US and east of the
Appalachians. Low to mid 60s dewpoints in the presence of a very
strong wind field will support a large area of severe weather threat
from the Southeast to the Carolinas and perhaps into parts of the
Mid-Atlantic. Storm mode and specific hazards will be impacted by
prior day convection and the overall evolution of the deepening
surface low and associated cold front, but a great enough threat
exists for 15% severe weather probabilities for D7/Wednesday.

..Bentley.. 02/27/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 281000
SWOD48
SPC AC 280958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Fri Feb 28 2025

Valid 031200Z - 081200Z

...DISCUSSION...
Medium-range guidance suggests that an initially zonal, intense
mid/upper jet across the western into central mid-latitude Pacific
may undergo considerable amplification into and through this period.
It remains a bit unclear how emerging waves will impact the
downstream pattern by the middle to latter portion of next week.

However, it still appears that one significant preceding short wave
trough, migrating inland of the Pacific coast by early Monday, will
progress into and across the southern Rockies, before accelerating east-northeastward through mid week. And guidance remains
suggestive that this will be accompanied by strong surface
cyclogenesis, perhaps most notably across portions of the east
central Great Plains toward the lower Great Lakes region late
Tuesday through Tuesday night. This may include an evolving warm
sector with intensifying low-level and deep-layer shear (in the
presence of southerly to southwesterly flow strengthening to 50-100
kt in the 850 to 500 mb layer), coincident with an influx of
moistening and destabilizing boundary-layer air off the northwestern
Gulf.

Spread typical at this extended time frame (day 5) lingers among the
various model output concerning the sub-synoptic, and even synoptic,
details across the southeastern Great Plains through Ohio Valley and
Southeast, which may considerably impact the severe weather risk
area and potential. However, the medium-range guidance depicts an
environment at least conditionally supportive of an organized severe
weather event, including potential for a few strong tornadoes and
damaging straight line winds.

It is possible, but perhaps a bit more uncertain, that this could
continue across parts of the southern and middle Atlantic Seaboard
on Wednesday.

..Kerr.. 02/28/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 011000
SWOD48
SPC AC 010958

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CST Sat Mar 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
Medium-range model output continues to indicate that strong
cyclogenesis will be underway to the lee of the Rockies by 12Z
Tuesday, as an intense mid/upper jet streak (probably including 100+
kt at 500 mb) noses northeast of the Texas Big Bend. The center of
an evolving broad and deep surface cyclone is generally forecast to
track from the central Great Plains through the lower Great Lakes
region by late Wednesday night, accompanied by a broad area of
intensifying lower-tropospheric wind fields. This probably will
include wind profiles characterized by strong deep-layer shear and
large, clockwise-curved low-level hodographs within the evolving
warm sector.

With guidance indicating an influx of lower/mid 60s F surface dew
points across at least the lower Mississippi Valley during the day
Tuesday, there appears considerable potential for sufficient
destabilization to support severe convection, including organizing
lines and supercells. However, uncertainties linger, perhaps
including some signal that some combination of low cloud cover,
limited surface heating and relatively warm, dry layers aloft with
modest lapse rates could impede destabilization. Variability among
the model output concerning the evolution of a number of synoptic
and sub-synoptic details could also considerably impact the extent
and location of stronger convective development.

In a broad sense, though, it still appears that the environment
centered across and just east of the lower Mississippi Valley will
become most conducive to thunderstorms potentially capable of
producing damaging straight-line winds and a few tornadoes Tuesday
into Tuesday night. This threat may wane by late Tuesday night
across the Tennessee Valley/eastern Gulf Coast states as Gulf
moisture return becomes cut off. However, an influx of low-level
moisture off the Atlantic might contribute to a rejuvenation strong
to severe thunderstorm potential ahead of an eastward advancing cold
front across parts of the southern and middle Atlantic Seaboard on
Wednesday.

..Kerr.. 03/01/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 020953
SWOD48
SPC AC 020951

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CST Sun Mar 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
As the center of a broad and deep surface cyclone migrates across
the lower Great Lakes region into Quebec Wednesday through Wednesday
night, strong deep-layer mean wind fields will spread east of the
Appalachians through the Atlantic Seaboard. This may include one
south to south-southwesterly core of 50-80 kt winds in the 850-500
mb layer, coincident with a weakening convective band, remnant from
storms developing on Tuesday across the lower Mississippi Valley. Destabilization with the approach of this activity may not be
sufficient to support substantive re-intensification as it
overspreads southern/middle Atlantic coastal areas during the day
Wednesday, but it might still be accompanied by locally strong to
severe wind gusts. In its wake, it also might not be out of the
question that destabilization beneath the mid-level dry slot could
become supportive of vigorous thunderstorm development during the
afternoon to the east of the Blue Ridge. However, the extent of
this potential remains unclear at this time.

In the wake of the cyclone, much of the nation, from the Pacific
coast into Great Plains and Southeast, appears likely to remain
under the influence of one prominent belt of westerlies emanating
from the mid-latitude Pacific. There is some signal in the
medium-range guidance that an embedded short wave trough might
support a developing frontal wave across the eastern Gulf Coast into
southern Atlantic Seaboard vicinity late this coming week into next
weekend. However, it is not yet clear that this will be strong
enough to support an appreciable risk for severe storms.

..Kerr.. 03/02/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 030955
SWOD48
SPC AC 030954

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CST Mon Mar 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
As a significant short wave trough pivots northeastward away from
the Mid Atlantic coast, models indicate that strong secondary
cyclogenesis may occur across and north of the Canadian Maritimes
late this week. In its wake, it appears that a confluent mid-level
flow regime will generally prevail, downstream of large-scale
troughing developing inland of the Pacific coast.

As this troughing continues eastward, models indicate that one
emerging short wave impulse may support fairly strong renewed
surface cyclogenesis to the lee of the Colorado Rockies on Thursday
into Friday. It appears this will occur before western Gulf
boundary-layer modification can support appreciable low-level
moistening on southerly return flow.

As the short wave accelerates into and through the confluent regime,
models indicate that the cyclone will weaken while migrating across
the central Great Plains into Ohio Valley. But a trailing cold
front may provide a focus for renewed frontal wave development, as
an upstream mid-level perturbation accelerates east of the Texas Big
Bend through the south Atlantic Seaboard by late next weekend. This
may be accompanied by moistening and destabilization across parts of
the central and eastern Gulf into south Atlantic Coast states on
Saturday into Sunday, in the presence of strengthening shear. This
could contribute to an environment at least marginally supportive of
organized strong thunderstorm development. However, barring
stronger cyclogenesis than currently forecast across the Southeast,
the severe weather potential still appears relatively low.

..Kerr.. 03/03/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 040954
SWOD48
SPC AC 040953

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Tue Mar 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
In the wake of renewed cyclogenesis across and north of the Canadian
Maritimes, it appears that a broad area of lower mid-level heights
will linger across the Great Lakes and Northeast late this week
through the coming weekend. This may contribute to the maintenance
of a confluent mid-level regime to the east of the Rockies, as much
of the western and southern U.S. remains under the influence of one
prominent belt of westerlies emanating from the mid-latitude
Pacific.

One embedded short wave trough digging into the Southwest with an
evolving mid-level low by early Friday is forecast to progress
across the southern Rockies by 12Z Saturday. Subsequent development
across and east of the southern Great Plains over the weekend into
early next week remains much more unclear. ECENS/ECMWF-based
guidance suggests that this feature emerges as an increasingly
sheared perturbation across the southern tier, supportive of only
low amplitude frontal wave development, until progressing across and
east of the south Atlantic Seaboard. GEFS/GFS-based guidance
forecasts similar shearing across the southern Great Plains, before
phasing with an amplifying wave within the cyclonic regime initially
confined to the Great Lakes vicinity. This would probably be
accompanied by more substantive cyclogenesis, with a moistening and destabilizing warm sector which could become supportive of organized
severe weather potential.

Thereafter, through the early to middle portion of next week, models
indicate that, as the persistent area of lower mid-level heights
retreats to the north and east, mid/upper flow may become more
supportive of strong cyclogenesis across Nebraska into the mid/lower
Missouri Valley by late next Tuesday night. However, it appears
that this will occur before the boundary-layer over the northwestern
Gulf recovers sufficiently to support a substantive moist return
flow.

..Kerr.. 03/04/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 051000
SWOD48
SPC AC 050959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Wed Mar 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
Cyclonic mid-level flow characterized by seasonably low heights
appears likely to linger across much of eastern Canada and the U.S.
Great Lakes vicinity through Northeast into this weekend, as broad
ridging builds in the subtropical and southern mid-latitudes. This
latter development is forecast to occur downstream of a significant
short wave trough emanating from the mid-latitude Pacific, with an
embedded closed low forming across the Southwest into southern
Rockies by 12Z Saturday.

Medium-range guidance indicates that this perturbation will remain
progressive, as a significant upstream short wave trough rapidly
progresses across the southern mid-latitude eastern Pacific, toward
the southern California coast over the weekend. It still appears
that the lead short wave will become increasingly sheared within a
confluent regime east of the Rockies through the Atlantic Seaboard.
The ECENS/ECMWF-based output and GEFS/GFS-based output remain varied
concerning how fast and the extent to which this occurs, with the
latter guidance still indicating a bit more notable surface wave
development along a frontal zone across the Gulf coast region.

There does appear a consensus that Gulf boundary-layer modification
may support a notable plume of returning low-level moisture ahead of
the mid-level wave, across Gulf coastal areas into and along the
frontal zone. Beneath initially steep lower/mid-tropospheric lapse
rates, guidance indicates that this will support modest potential
instability in the presence of strong deep-layer shear. This could
lead to a corridor of vigorous thunderstorm development on Saturday,
with stronger convection possibly becoming supportive of severe hail
and perhaps locally strong surface gusts. It remains unclear
whether this will setup near immediate upper Texas through north
central Gulf coastal areas, or as far north as the Ark-La-Tex
through central/northern Mississippi and Alabama. Stronger frontal
wave development would probably support more substantive and further
inland severe weather potential, which could spread across parts of
the southern Atlantic Seaboard on Sunday. Due to the low
predictability at this time, and the somewhat marginal nature of the
severe threat, severe weather probabilities are being maintained at
less than 15 percent.

Into early next week and beyond, as the lower heights shift out of
the Northeast, a series of amplified, but progressive waves within
the westerlies emanating from the Pacific may contribute to
periodic, potentially significant cyclogenesis to the lee of the
Rockies, However, in the wake of the lower latitude weekend trough,
low-level moisture return off the Gulf may be initially limited.

..Kerr.. 03/05/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 061001
SWOD48
SPC AC 060959

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CST Thu Mar 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
Medium-range guidance continues to exhibit considerable spread
concerning short wave developments within the evolving pattern
across North America late this coming weekend through the middle of
next week. Concerning an initial perturbation likely to be slowly
progressing across the southern Great Plains at the outset of the
period, latest model guidance now appears to maintain a less
sheared/more substantive (but positively tilted) wave across the
northeastern Gulf/South Atlantic Seaboard late this weekend into
early next week. However, it still appears that associated frontal
wave development will remain subdued, at least until it shifts
offshore of the Atlantic coast, which may tend to minimize the risk
for severe storms across the Southeast.

Thereafter, through the middle to latter portion of next week, it
appears that another notable short wave trough will emerge from the
southern mid-latitude Pacific and provide support for cyclogenesis
to the lee of the southern Rockies by Wednesday. This may quickly
be followed by a much more vigorous and amplified wave, and more
prominent cyclogenesis next Thursday into Friday. However, in the
wake of the lower latitude weekend trough, low-level moisture return
off the Gulf may be initially limited for the trailing perturbation,
and the timing of the rapidly following wave might not be optimal
with regard to subsequent inland moisture return.

At least some risk for organized severe convection may materialize
to the east of the Rockies next Wednesday through Thursday night.
However, the extent and location remain uncertain at this time.

..Kerr.. 03/06/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 070910
SWOD48
SPC AC 070909

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0309 AM CST Fri Mar 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
A progressive upper pattern is forecast during the Day 4-8 period.
An upper shortwave trough over the Southeast will move offshore the
Atlantic coast on Day 4/Mon. In its wake, low-amplitude upper
ridging is forecast from the southern Plains into the Southeast
through Day 5/Tue. Severe thunderstorm potential will be low during
this time as surface high pressure near the Gulf coast maintain a
dry continental airmass.

By Day 6/Wed, an upper trough over the southern Rockies and northern
Mexico will shift east across the southern Plains to the Sabine
Valley vicinity. Enhanced southwesterly deep-layer flow will develop
ahead of the trough across TX into the Lower MS Valley. Surface
cyclogenesis is currently forecast to remain modest, but southerly
low-level flow will transport Gulf moisture northward across the
south-central states. Higher-quality moisture is expected to remain
offshore or very near the TX/LA coast, with low 60s F dewpoints
possible across parts of east TX and LA ahead of an eastward
advancing cold front. Thunderstorm potential will accompany this
system, but moisture return will likely remain sub-optimal for a
greater severe risk.

By the end of the period, around Day 8/Fri, medium range guidance
develops a larger-scale, deepening trough ejecting into the Plains
and Upper Midwest vicinity. While some severe potential may increase
around the Friday time frame, large spread among guidance with
regards to timing and placement of the upper trough and key surface
features lends to low predictability. Trends will be monitored over
the coming days and outlook areas may become necessary if confidence
increases.

..Leitman.. 03/07/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 080921
SWOD48
SPC AC 080919

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0319 AM CST Sat Mar 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
...Day 5/Wed - ArkLaTex Vicinity...

Severe thunderstorm potential may increase around Day 5/Wednesday as
a shortwave upper trough over the Southwest and northern Mexico
develops east into the southern Plains. The GFS model suite is much
more aggressive in the strength of this system compared to the
ECMWF, with the GFS depicting a negative-tilt trough with a
southwesterly jet streak overspreading the ArkLaTex vicinity
Wednesday evening. The ECMWF on the other hand depicts a
positive-tilt upper trough located further south, and with model
soundings depict stronger capping. While some northward moisture
return from the western Gulf is likely to occur across east TX and
the ArkLaTex vicinity, large spread in surface features also is
apparent. Severe probabilities may be needed at some point across
the region, but uncertainty is still too high to delineate
unconditional 15 percent severe probabilities.

...Day 7-8/Fri-Sat - Mid/Lower MS Valley into the Southeast...

Low predictability due to large spread continues in medium-range
guidance for the end of the period. However, forecast guidance
generally depicts a strong springtime large-scale upper trough
ejecting across the Plains into the eastern U.S. late in the period.
This strong upper-level trough will result in a deepening surface
cyclone over the Plains moving east/northeast into some portion of
the Midwest, allowing Gulf moisture to spread northward centered
roughly on the Mid/Lower MS Valley (Fri) into the Southeast (Sat).
Given large model disparity in the placement and timing of key
features, confidence/predictability is too low to delineate severe probabilities at this time, but outlook areas will likely be needed
in subsequent outlooks anywhere from the ArkLaTex and Deep South
into the Midwest.

..Leitman.. 03/08/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 090837
SWOD48
SPC AC 090835

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0335 AM CDT Sun Mar 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
...Day 4/Wed - ArkLaTex vicinity...

A shortwave upper trough is forecast to develop east from the
southern Rockies/northern Mexico to the Lower MS/TN Valley vicinity
on Wednesday. Forecast guidance generally keep the stronger midlevel
jet streak over central/southern TX into the Lower MS Valley.
Surface cyclogenesis is expected to remain modest, but some increase
in southerly low-level flow across the western Gulf with transport
mid 50s to low 60s F dewpoints into the ArkLaTex and Ozark Plateau
region. Cooling aloft will support steepening midlevel lapse rates,
and this will contribute to modest elevated instability. Forecast
soundings suggest boundary layer inhibition will likely subdue
potential for surface-based convection. Nevertheless, some potential
for isolated strong to severe storms capable of producing hail
appears possible. Overall confidence in unconditional 15 percent
probabilities is too low to delineate any severe area at this time,
but some low-end probabilities may become necessary in subsequent
outlooks.

...Day 6/Fri - Mid to Lower MS Valley vicinity...

A powerful upper cyclone and attendant trough is expected to develop
east across the Plains toward the MS Valley on Friday. An intense
southwesterly jet (100+ kt at 500 mb) is expected to be oriented
from the southern Plains to the Mid-MS Valley by Friday evening.
Meanwhile, a rapidly intensifying surface cyclone will shift
northeast from the central Plains to the Upper Midwest vicinity
through the period. Strong southerly low-level flow ahead of this
low and an attendant eastward-advancing cold front will support
rapid northward transport of Gulf moisture. While details regarding
quality of northward moisture transport remain, this overall pattern
will be very favorable for a regional severe weather episode from
late Friday afternoon into early Day 6/Sat morning.

Overall, cross-model consistency has improved compared to the past
couple of days, and guidance generally appears to be converging on
similar solutions. When compared with the operational ECMWF, the
operational GFS remains a bit further north with the placement of
the low-level and upper-level cyclones, as well as northward extent
of better moisture return. However, the GEFS and EPS ensemble means
are quite similar. While this indicates there is still a moderate
degree of spread in the north and east extent of severe potential,
the envelop is narrowing, and a broad area favorable for an
all-hazards severe episode is expected on Friday/Friday night,
centered on the Mid to Lower MS Valley vicinity. This trends is also
aligned with SPC and NSSL experimental machine learning guidance.
Given uncertainties still exist regarding timing and location of key
features, as well as with northward extent of deeper moisture
return, this area is likely to change/shift some over the coming
days as details become better resolved (and higher probabilities
will likely become necessary as well).

...Day 7/Sat - Southeast vicinity...

While the upper cyclone from Day 6/Fri will lift northeast over the
Upper Great Lakes into Canada on Saturday, the base of the
larger-scale upper trough over the southern Plains will eject east
over the Southeast states. Convection will likely already be
occurring ahead of the cold front, and will have access to deeper
Gulf moisture downstream across MS/AL. The north and east extent of
severe potential is uncertain as the evolution of the system on
Friday will impact downstream potential. Nevertheless, the overall
pattern will be favorable for a continuation of severe potential
into Saturday given strong vertical shear overlapping a seasonally
moist and at least modestly unstable airmass.

...Day 8/Sun - Mid-Atlantic vicinity...

An upper trough will continue to shift east across the eastern U.S.
on Sunday. While strong deep-layer flow will overspread the region
in conjunction with a moist boundary-layer ahead of an
eastward-advancing cold front, it is uncertain how much
destabilization will be able to occur. Trends will be monitored for
possible severe probabilities in the coming days, but current
predictability is low.

..Leitman.. 03/09/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 100855
SWOD48
SPC AC 100854

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Mon Mar 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
...Day 4/Thu - Southeast...

A shortwave upper trough will move across the Southeast on Thursday.
Stronger deep-layer flow will mainly be focused over the Gulf.
However, cooler temperatures aloft will support weak instability and
a strong storm or two may occur over portions of AL/GA and the FL
Panhandle. Overall severe potential appears limited.

...Day 5/Fri - ArkLaTex to the Mid/Lower MS Valley vicinity...

A regional outbreak of severe storms is forecast late Friday
afternoon into the overnight hours. An intense upper cyclone will
deepen as it ejects northeast from the central/southern Plains to
the Upper Midwest by Saturday morning. A 100+ kt 500 mb jet streak
will move across OK into the Ozark Plateau during the late afternoon
and evening, before lifting north across the Mid-MS Valley
overnight. At the surface, a rapidly deepening surface low will move
across the central Plains to the Upper Midwest, with a cold front
surging east across the region from late afternoon into Saturday
morning.

Deeper Gulf moisture will be confined to the I-20 corridor Friday
morning. However, intense low-level flow will quickly transport
moisture northward through the mid-MS Valley. Surface dewpoints
greater than 60 F will likely remain south of the MO Bootheel
vicinity, with a broader area of more modest moisture as far north
as northeast IA/southwest WI and northern IL. While moisture will be
less favorable with northward extent, strong large-scale ascent,
intense deep-layer flow and a surging cold front will likely be
sufficient for severe convection even amid weak instability. Further
south from the ArkLaTex vicinity to the Lower MS Valley, better
quality moisture is expected to overlap intense shear. Overall, this
pattern will support all severe hazards, with a potential mixed mode
evolution (QLCS and supercells).

The north and east extent of severe potential remains a bit
uncertain either due to moisture concerns and/or spread among
various guidance in timing and position of key features. Severe
probabilities will likely be refined over the coming days as these
features become better resolved.

...Day 6/Sat - Southeast...

The Upper Midwest cyclone will eject northeast into Ontario on
Saturday. Meanwhile the base of the larger-scale upper trough over
the Plains ejects east toward the Lower MS Valley and Southeast.
This will maintain strong deep-layer southwesterly flow across the
region, with an intense low-level jet expected to develop by late
afternoon as stronger height falls overspread the Deep South.
Ongoing convection at the beginning of the period from the Lower OH
Valley toward northern MS/LA adds some uncertainty regarding how the
airmass will destabilize (especially with northward extent).
However, it appears likely that a very favorable corridor of rich
boundary layer moisture will overlap strong shear from
central/southern MS into northern AL ahead of a cold front expected
to surge across the area during the evening. This overall pattern
appears favorable for both supercells and an eventual QLCS.

...Day 7/Sun - Eastern states...

The upper trough over the central U.S. will lift northeast over the
eastern states on Sunday. Some severe potential is possible given
strong deep-layer flow atop a moist boundary layer ahead of the eastward-advancing cold front. However, destabilization may be
limited by widespread training precipitation.

..Leitman.. 03/10/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 110851
SWOD48
SPC AC 110849

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0349 AM CDT Tue Mar 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
...Days 4-6/Fri-Sun - Mid/Lower MS Valley to the Southeast and
Mid-Atlantic...

An intense spring storm system will deliver a multi-day severe
weather episode to portions of the central and eastern U.S.
beginning Friday and continuing through the weekend. All severe
thunderstorm hazards are expected, including widespread damaging
winds, tornadoes (some strong), and large hail.

On Friday, an anomalously intense upper cyclone is forecast to
deepen as it tracks northeast across the southern/central Plains to
the Upper Midwest. An intense jet streak (greater than 100 kt at 500
mb) will overspread the Ozarks and Mid-MS Valley during the
afternoon into the overnight hours. Likewise, a low-level jet will
intensify Friday night to 65+ kt. As intense surface cyclogenesis
occurs, southerly low-level flow will transport modest moisture as
far north as eastern IA, southeast MN and southern WI. Deeper
boundary-layer moisture will remain focused southward from the
Mid-South toward the Lower MS Valley/central Gulf coast.
Nevertheless, strongly forced convection within intense deep-layer
flow will pose a widespread risk for severe (potentially significant
severe) thunderstorm winds and tornadoes from late afternoon into
the overnight hours across a large area centered on the Mid/Lower MS
Valley vicinity.

On Saturday, the upper cyclone over the Upper Midwest will lift
northeast into Ontario, but a larger-scale upper trough will remain
over the Plains. The Plains trough will intensify and spread east
toward the MS/OH Valleys. This will maintain the eastward
progression of a strongly forced line of convection from the Ohio
Valley south/southwest into the Deep South/central Gulf coast
vicinity through Saturday night. Portions of the Deep South into GA
may see multiple rounds of severe convection with a mix of both
supercell and QLCS storm modes potentially moving across the region,
posing a concern for damaging tornadoes and swaths of severe winds.

On Sunday, the system will continue to shift east, with a moist
airmass and strong deep-layer flow continuing to support a line of
convection producing damaging winds into the Carolinas and
Mid-Atlantic vicinity.

Outlook areas will continue to be refined over the coming days as
key features become better resolved.

..Leitman.. 03/11/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 120846
SWOD48
SPC AC 120845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Wed Mar 12 2025

Valid 151200Z - 201200Z

...SEVERE WEATHER OUTBREAK POSSIBLE ON D4/SAT...

...DISCUSSION...
...Day 4/Sat - Central Gulf Coast States to the Ohio Valley...

A strong large-scale upper trough is forecast to quickly move across
the Plains to the MS Valley on Saturday. An intense jet streak will
move across the Deep South into the OH Valley as this occurs. At the
surface, a low secondary to the 980 mb low over the Upper Midwest is
forecast to develop during the late morning/early afternoon across
the mid-South. This will aid in further northward transport of rich
Gulf moisture into portions of the Lower MS Valley and TN Valleys.
Atop this moisture-primed boundary layer, cold 500 mb temperatures
are forecast. This may support fairly steep lapse rates, which would
foster moderate instability across portions of MS/AL amid supercell
wind profiles. However, some uncertainty remains tied to the
evolution of convection in the Day 3/Fri period into the morning
hours of Saturday. Some forecast guidance suggests a relatively
pristine warm sector will be maintained, or if only isolated
convection develops overnight/early Saturday, recovery could occur.
If this scenario unfolds, a concerning severe weather setup
supporting all-hazard severe could unfold across portions of
LA/MS/AL through the day and into evening, and eventually spreading
east into GA overnight. Trends will be monitored closely over the
coming days and further adjustments to the 30 percent/Enhanced risk
area may be needed in future outlooks.

With northward extent, instability will become more limited.
Nevertheless, sufficient moisture amid intense deep-layer flow will
support swaths of strong/damaging winds into the Ohio Valley and
portions of the central Appalachians Saturday and Saturday night.
Higher outlook probabilities may be needed in subsequent outlooks if
confidence increases.

...Day 5/Sun - North Florida into the Carolinas and Mid-Atlantic...

A strong upper trough will shift east across the Midwest and
Southeast on Sunday. Strong deep-layer southwesterly flow ahead of
the trough will overspread much of the eastern U.S. atop a moist
boundary layer. Bands of convection will likely produce swaths of
strong to severe gusts ahead of an eastward-advancing cold front.

...Days 6-8/Mon-Wed...

An upper trough will move offshore over the Atlantic on Monday,
while a broad upper ridge spreads across the Plains in its wake.
Another large-scale upper trough will move across the western U.S.
on Tuesday, ejecting across the Plains and into the MS Valley on
Wednesday. Some severe potential could return to parts of the
central or south-central states toward the end of the period with
this system, but current model forecasts suggest moisture return in
the wake of the Day 4/5 system will remain poor. Trends will be
monitored over the coming days.

..Leitman.. 03/12/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 130834
SWOD48
SPC AC 130832

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0332 AM CDT Thu Mar 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
...Day 4/Sun - Eastern U.S....

A large-scale upper trough near the MS Valley Sunday morning will
develop east to the Appalachians by early Monday. Strong deep-layer south/southwesterly flow on the eastern side of the upper trough
will overspread much of the eastern U.S. Convection will likely be
ongoing Sunday morning from the Upper OH Valley into GA and northern
FL. This activity will move into a moist airmass, characterized by
60s F dewpoints from north FL toward the Chesapeake Bay vicinity
(50s F dewpoints further north into PA/NJ). Instability will be
greatest where deeper boundary layer moisture is forecast, but given
intense deep-layer flow, organized convection is expected with even
very modest instability. While linear convection producing damaging
gusts will be the main hazard for much of the region, tornado
potential will exist where sufficient boundary layer moisture
exists, most likely from the Carolinas southward.

...Days 6-7/Tue-Wed - OK/KS into the MS/OH/TN Valleys...

Another large-scale upper trough is forecast to move across the West
and into the Plains on Tuesday into early Wednesday, and then into
the Midwest by Thursday. This will bring some potential for severe
storms. However, a prior cold frontal intrusion deep into the Gulf
and surface high pressure east of the MS River in the wake of the
Day 4/Sun upper trough will limit moisture return into the
southern/central Plains on Tuesday. Modest moisture return is
possible further southeast on Wednesday, but forecast guidance
currently is unremarkable. Trends will be monitored, but the
probability for any more an isolated/marginal severe appears low at
this time.

..Leitman.. 03/13/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 140859
SWOD48
SPC AC 140858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Fri Mar 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
A broad anti-cyclonic flow pattern is forecast to develop across the continental U.S. on Monday, as surface high pressure moves across
the southern and eastern U.S. On Tuesday into Wednesday, a mid-level
trough is forecast to move eastward across the western and central
U.S. Weak low-level moisture return is expected to take place across
the south-central U.S. ahead of the system. On Tuesday, thunderstorm development appears most likely across eastern parts of the southern
and central Plains. By Wednesday, model forecasts have surface
dewpoints reaching the 50s F in parts of the lower Mississippi
Valley and Ark-La-Tex. Thunderstorms will be possible on Wednesday
along this corridor. As the system moves across the south-central
U.S. from Tuesday into Wednesday, a severe threat may develop.
However, medium-range model forecasts suggest that instability will
remain relatively weak, suggesting that any severe threat should be
isolated and marginal.

...Thursday/Day 7 and Friday/Day 8...
From Thursday into Friday, a mid-level trough is forecast to move
from the mid Mississippi Valley quickly eastward to the western
Atlantic. During the day on Thursday, thunderstorm development will
be possible ahead of the trough in parts of the eastern U.S. The
return of low-level moisture ahead of the system, and the resultant instability, is forecast to remain relatively weak. For this reason,
any severe threat that develops on Thursday is expected to be
marginal.

..Broyles.. 03/14/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 150859
SWOD48
SPC AC 150857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Sat Mar 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
At mid-levels, a trough is forecast to move eastward across the
central U.S. on Tuesday and Wednesday. Ahead of the system,
low-level moisture is forecast to return northward into the lower to
mid Mississippi Valley, with surface dewpoints reaching the 40s and
50s F. This should contribute to an axis of weak instability by
Tuesday afternoon. Along and near this axis, isolated to scattered thunderstorms are expected to develop from parts of Oklahoma to
Iowa. The chance for storms is expected to continue ahead of the
trough, as it moves into the mid Mississippi Valley on Wednesday. A
severe threat will be possible near the moist axis in the afternoon.
However, relatively low surface dewpoints and very weak instability
should keep any severe threat isolated and marginal.

...Thursday/Day 6 to Saturday/Day 8...
The mid-level trough in the Mississippi Valley is forecast to move
eastward to the Atlantic Seaboard by Thursday night, as another
trough moves into the High Plains. This second trough is forecast to
move across the central U.S. on Friday, reaching the eastern U.S. on
Saturday. Some moisture return is forecast late in the week in the
western Gulf Coast states. Although an isolated severe threat would
be possible within this moist airmass, predictability concerning any
severe threat magnitude is substantial at this range.

..Broyles.. 03/15/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 160858
SWOD48
SPC AC 160856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Sun Mar 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
...Wednesday/Day 4 to Friday/Day 6...
A mid-level trough is forecast to move northeastward into the upper
Mississippi Valley on Wednesday. Ahead of the trough, a narrow axis
of moisture and weak instability is forecast from the western Great
Lakes into the lower Ohio Valley. This corridor of low-level
moisture will be the favored location for convective development
Wednesday afternoon. Surface dewpoints along the moist axis are only
expected to be in the 40s to lower 50s F. In spite of this, the exit
region of the mid-level jet is forecast to overspread the region
during the mid to late afternoon. This will provide strong lift and
deep-layer shear, sufficient for an isolated severe threat. Any
severe threat should remain marginal.

On Thursday, the trough is forecast move eastward through the Ohio
and Tennessee Valleys, as a cold front advances to near the Atlantic
Seaboard, from the eastern Carolinas into the Mid-Atlantic. Isolated
severe storms will again be possible along or ahead of the front
during the mid to late afternoon, but any threat is expected to be
marginal.

On Friday, a mid-level trough is forecast to move eastward into the
central states, where isolated convection will be possible. However,
moisture return is expected to be confined to the Texas Coastal
Plain, which will be a severe threat limiting factor.

...Saturday/Day 7 and Sunday/Day 8...
On Saturday, the trough is forecast to de-amplify and move into the northeastern U.S. as a broad low-amplitude cyclonic flow pattern
develops over much of the U.S. Moisture return is expected to take
place over the western Gulf Coast on Saturday and across the
southern Plains on Sunday. Some models suggest that a trough will
take shape in the Great Plains on Sunday, with a cluster of storms
forming ahead of the system Sunday afternoon. These storms would
develop along the northern edge of the stronger instability from
Oklahoma into Arkansas, expanding Sunday evening across the lower to
mid Mississippi Valley. If this scenario where to verify, then a
severe threat would be possible with the stronger storms within the
MCS. However, at this extended range, the magnitude and spatial
extent of any severe threat remains considerably uncertain.

..Broyles.. 03/16/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 170858
SWOD48
SPC AC 170857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Mon Mar 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
On Thursday, a trough at mid-levels will move eastward into the
Appalachians, as a cold front advances quickly eastward across the
Atlantic Coastal states. Isolated strong gusts may occur with
convection that develops along or ahead of the front. The threat is
expected to be marginal.

On Saturday and Sunday, a mid-level trough is forecast to quickly
move from the High Plains to the East Coast. A moist airmmass in the
Gulf Coast region is forecast to remain largely in place as the
system passes to the north. This will likely limit any severe
potential.

...Sunday/Day 7 and Monday/Day 8...
From Saturday night into Sunday, moisture advection is forecast to
increase considerably over the southern Plains, as a mid-level
trough moves quickly southeastward across the central U.S.
Medium-range models suggest that the northern edge of the moist
airmass will be located from the Red River Valley eastward into the
lower Mississippi Valley by Sunday afternoon. Thunderstorm
development will be possible along this east-to-west corridor during
the late afternoon and evening, where the models suggest that
moderate instability and strong deep-layer shear will be in place.
Model spread appears low enough to add a 15 percent area, centered
on the Ark-La-Tex for Sunday.

On Monday, the trough is forecast to move eastward across the Ohio
and Tennessee Valleys, as a cold front advances quickly toward the
Atlantic Seaboard. Thunderstorms with an isolated severe threat will
be possible along and near the front during the afternoon, but
predictability is low concerning the timing of the front, and its
associated trough.

..Broyles.. 03/17/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 180852
SWOD48
SPC AC 180850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Tue Mar 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
...Friday/Day 4 to Saturday/Day 5...
On Friday and Saturday, a shortwave mid-level trough will move
eastward from the Great Plains to the Eastern Seaboard, as a long
fetch of west-northwest flow develops over much of the continental
U.S. Isolated convection may develop ahead of the trough, but
instability will likely be insufficient for a severe threat. In the
wake of this system, low-level moisture return will begin along the
western Gulf Coast. By Saturday, surface dewpoints are expected to
be the upper 50s and lower 60s F over the Texas and Louisiana
Coastal Plain.

...Sunday/Day 6 to Tuesday/Day 8....
On Sunday, moisture advection is forecast to increase over eastern
parts of the southern Plains into the Ark-La-Tex. A mid-level trough
is forecast to move across the central U.S. Ahead of the trough,
moderate instability is forecast to develop across much of a moist
airmass located from the southeastern third of Texas northeastward
into the Ark-La-Tex. On Sunday, thunderstorms with a threat for
isolated large hail and severe gusts are expected to develop along
the northern edge of the moist sector, with a complex of storms
moving southeastward across the Sabine and lower Mississippi Valleys
overnight.

On Monday and Tuesday, the mid-level trough is forecast to move into
the eastern U.S., as a cold front advances southward to near the
Gulf Coast. Although isolated storms could develop in the southern
Gulf Coast states, limited large-scale ascent is expected to be
problematic concerning an organized severe threat.

..Broyles.. 03/18/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 190852
SWOD48
SPC AC 190850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Wed Mar 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
...Saturday/Day 4 to Sunday/Day 5...
A mid-level trough will move through the central U.S. on Saturday
and Sunday, as moisture advection takes place across the southern
Plains, lower Mississippi Valley and Ark-La-Tex. Thunderstorm
development will likely take place ahead of the trough on Sunday
afternoon and evening, along the northern edge of the moist airmass
from the Red River Valley eastward into the lower Mississippi
Valley. A threat for large hail and severe wind gusts will be
possible within the more organized components of a developing MCS.
The MCS is forecast to move southeastward through the lower
Mississippi valley during the overnight period.

...Monday/Day 6 to Wednesday/Day 8...
On Monday, the trough is forecast to become amplified across the
Ohio and Tennessee Valleys, as a cold front moves southward through
the Gulf Coast states. Isolated severe storms could occur near the
central Gulf Coast early in the day, but the majority of the storms
are expected to move offshore into the Gulf. On Tuesday and
Wednesday, surface high pressure is forecast to settle over the
eastern half of the nation. This dry and cool airmass will make
conditions unfavorable for thunderstorms over most of the
continental U.S.

..Broyles.. 03/19/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 200900
SWOD48
SPC AC 200858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Thu Mar 20 2025

Valid 231200Z - 281200Z

...DISCUSSION...
...Sunday/Day 4 and Monday/Day 5...
A large-scale cyclonic flow pattern will be in place across much of
the continental U.S. on Sunday. An upper-level low will develop over
the Great Lakes, as an associated trough moves southeastward from
the Great Plains to the Mississippi Valley. A cold front is forecast
to move southeastward into the Ozarks. Ahead of the front, moisture
advection is forecast to occur over the Sabine and lower Mississippi
Valleys, where surface dewpoints will likely be in the 60s F and
moderate instability is expected to develop. Scattered thunderstorms
appear likely to initiate ahead of the front Sunday evening from the
Sabine River Valley northeastward into the Tennessee Valley, with an
MCS developing Sunday evening. Moderate deep-layer shear will likely
support severe thunderstorm development, with a potential for severe
wind gusts, isolated large hail. A tornado threat may also develop.

A cold front is forecast to move through the Gulf Coast region
Sunday morning. Isolated severe storms could develop ahead of the
front early in the day from the Texas Coast eastward to the central
Gulf Coast and Florida Panhandle. Predictability remains low
concerning where the greatest severe threat will be along this
corridor. The severe threat should end during the day as the front
moves southward into the Gulf.

...Tuesday/Day 6 to Thursday/Day 8...
On Tuesday, a mid-level trough is forecast to dig southeastward into
the Mississippi Valley. At the surface, a moist airmass will remain
over the Gulf Coast region. Isolated strong to severe storms could
occur along the northern edge of this moist airmass. The greatest
potential for severe could be across the Sabine River Valley, where
some solutions have moderate instability Tuesday afternoon. This
appears to be a conditional severe threat, and predictability is
low.

From Wednesday into Thursday, a relatively dry airmass is forecast
over much of the nation. The exception could be across south Texas,
where thunderstorm development will be possible. Although an
isolated severe threat would be possible there, predictability at
this extended range in the forecast cycle is low.

..Broyles.. 03/20/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 210853
SWOD48
SPC AC 210851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Fri Mar 21 2025

Valid 241200Z - 291200Z

...DISCUSSION...
Models suggest that a west-to-east cold front will move slowly
southward across the Gulf Coast states/Southeast on Monday/Day 4, as
an upper trough shifts slowly eastward across the eastern CONUS.
Ample instability should evolve along the front to support afternoon
storm development, but quasi-unidirectional flow with height, weak
at low levels, may hinder prospects for severe storms despite ample
mid-level flow. At this time, while some severe risk is apparent,
potential appears too low to warrant inclusion of a risk area at
this time.

The front should continue shifting southward while weakening Days
5-6 (Tuesday and Wednesday), as weak surface high pressure settles
into the eastern states. While thunder will be possible near the
Gulf Coast Tuesday, and lingering over Florida Thursday, severe risk
appears to be low.

Model differences begin to increase substantially beyond
Wednesday/through the end of the period. The ECMWF depicts a
substantial mid-level short-wave trough and accompanying surface
system moving into the Plains Day 8, while quasi-zonal flow aloft is
depicted by the GFS. As such, predictability concerns preclude
assessment of severe potential beyond Day 6.

..Goss.. 03/21/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 220838
SWOD48
SPC AC 220837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Sat Mar 22 2025

Valid 251200Z - 301200Z

...DISCUSSION...
Medium-range models are in reasonable agreement into the Day 6
(Thurs. Mar. 27) time period, after which divergence in solutions at
the synoptic scale begins to increase. This lack of predictability
in the latter half of the period results in lack of confidence with
respect to any assessment of severe-weather potential.

Through the first half of the period, severe-weather potential
appears limited -- particularly Days 4-5 (Tuesday and Wednesday of
next week). During this time period, an upper trough will advance
slowly eastward across the eastern U.S., with the main surface
baroclinic zone suppressed southward into the Gulf of America and
high pressure building in its wake.

Day 6, hints of a rather weak upper disturbance moving into the
southern Plains could support local/limited severe potential with a
few strong storms, but certainly not appearing sufficient in nature
to warrant an areal inclusion at this time.

..Goss.. 03/22/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 230904
SWOD48
SPC AC 230902

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0402 AM CDT Sun Mar 23 2025

Valid 261200Z - 311200Z

...DISCUSSION...
Medium-range models appear to be in reasonable agreement with
large-scale features through Day 5 (Thursday Mar. 27), during which
time overall severe risk should remain generally tempered. A weak
surface warm front should lie from northwest-to-southeast across
Texas Day 4/Wednesday, with a secondary boundary lying
northwest-to-southeast from the northern High Plains to Kansas.
However, background ridging over the Rockies/western portions of the
Plains should suppress convection to some degree. This, along with
modest mid-level flow (generally 20 to 30 kt) expected across the
area will limit risk, though a few stronger central/southern High
Plains storms may evolve during the afternoon and evening.

On Day 5/Thursday, a weak southern-stream trough is forecast to
undercut the northern-stream ridge, shifting into the southern
Plains with time. While overall instability should once again
remain limited -- largely due to still-limited moisture return -- a
few stronger storms will again be possible during the afternoon and
evening. One area of more focused potential for a few storms
appears to exist over eastern portions of Nebraska and Kansas near
the slowly northward-advancing warm front; a few stronger afternoon
storms may also occur across portions of western Texas.

Day 6/Friday, models begin to diverge more substantially, with this
divergence increasing through the end of the period. Models hint
that a stronger trough may begin advancing across the West, and
into/across the Plains Days (next weekend). This would be
associated with stronger surface development, more robust northward
moisture transport, and more favorable flow aloft. Thus, while
severe risk appears likely to increase, differences in the models
with respect to details of this evolution preclude any confident
introduction of risk areas at this time.

..Goss.. 03/23/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 240904
SWOD48
SPC AC 240902

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0402 AM CDT Mon Mar 24 2025

Valid 271200Z - 011200Z

...DISCUSSION...
Medium-range/global models have come into reasonable agreement with
respect to the most recent run, signaling toward heightened severe
risk over the upcoming weekend across central portions of the
country.

Days 4-5 (Thursday/Friday), locally strong storms will be possible
across a rather broad portion of the central of the country, from
the Upper Midwest to the southern Plains Day 4/Thursday, and the
Plains into the Ohio Valley Friday. This will occur as a
weak/slow-moving southern stream trough moves slowly
east-northeastward across this region. Somewhat limit risk, over a
broad geographic area, precludes introduction of any 15% risk areas
either of these two days.

Meanwhile, the primary synoptic pattern -- even early in the period
-- favors a persistent lee surface low/trough over the High Plains.
This will allow southerly low-level flow to evolve/expand across
almost all of the central and eastern portions of the country as a
warm front shifts northward into the northern CONUS.

By early Saturday/Day 6, height falls associated with a
strengthening trough moving across the Intermountain West should
begin to spread into the Plains, with the trough itself currently
expected to reach the High Plains. This will result in an eastward
advance of a surface low front out of the High Plains and across the
central Plains states through the evening/overnight. With a
moistening pre-frontal boundary layer ahead of the advancing system,
and increasing flow aloft, the overall setup will favor increasing
severe potential, with all-hazards possible.

Day 7/Sunday, eastward advance of the synoptic-scale features will
continue, along with some continued strengthening. With continued
moistening of the pre-frontal warm sector supporting afternoon
destabilization, along with increasing deep-layer flow, a broad area
of severe risk seems likely to evolve -- centered over the Mid and
Lower Mississippi/Lower Ohio/Tennessee Valleys. Again -- all severe
weather hazards would be possible.

Monday, the primary focus for convective potential will shift east
of the Appalachians. Here, weaker low-level moisture (and thus less
robust destabilization potential) is expected at this time.
Therefore, while severe risk may evolve, thermodynamic uncertainty
precludes initiation of a risk area for Day 8/Monday.

..Goss.. 03/24/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 250911
SWOD48
SPC AC 250909

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0409 AM CDT Tue Mar 25 2025

Valid 281200Z - 021200Z

...DISCUSSION...
Medium-range models appear to be in reasonably good agreement into
the Day 7 period (Monday March 31), with respect to
evolution/progression of large-scale features.

Day 4/Friday, a southern-stream trough is forecast to continue
moving slowly eastward across the south-central states, reaching the
lower Mississippi Valley Saturday morning. Showers and
thunderstorms will accompany this feature, but the lack of robust
CAPE/shear likely to be associated with this feature suggests that
severe potential should remain subdued.

Farther north, weak disturbances moving through anticyclonic flow
aloft across the Upper Midwest/Upper Great Lakes/Ohio Valley will
likely combine with warm advection near the northward-advancing warm
front to support areas of deep convection, with some potential for
hail. Risk however appears too low to warrant an areal inclusion.


Saturday (Day 5), an upper trough will continue advancing across the
Rockies. However, models forecast the main surface low to remain
over the eastern Colorado vicinity into the evening hours, with a
capped warm sector residing across eastern Kansas/Oklahoma/Texas and
the Ozarks area (i.e. yesterday's Day 6 outlook area) in a zone of
subsidence in the wake of the slow-moving southern-stream trough.
As such, storm initiation now appears likely to remain largely
hindered through Sunday morning.

The primary severe risk appears likely to evolve Sunday/Day 6, from Missouri/Arkansas/northern Louisiana, spreading eastward through the
day, and eventually approaching the west slopes of the Appalachians.
As the western U.S. upper trough emerges into the Plains,
supporting deepening of surface low pressure, a moist warm sector
will destabilize through the day, likely yielding storm development
initially west of the Mississippi Valley, and then spreading
eastward through the evening. The favorable thermodynamic
environment will combine with strong/veering flow through the middle troposphere, suggesting of severe storms including supercells, and
attendant, all-hazards severe potential.

By Monday, models begin to diverge with respect to speed of
surface-frontal advancement east of the Appalachians. Still, enough destabilization should occur east and southeast of the front to
allow storms to spread across the Southeast, along with attendant
severe risk.

Tuesday, model differences continue to increase, with the front
residing off the Atlantic and Gulf Coasts per the GFS, while
lingering over parts of the Southeast and the Gulf Coast region per
the ECMWF. Given the uncertainty/predictability issues, no risk
areas will be included.

..Goss.. 03/25/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 260906
SWOD48
SPC AC 260904

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0404 AM CDT Wed Mar 26 2025

Valid 291200Z - 031200Z

...DISCUSSION...
Medium-range models appear to be in reasonable agreement through Day
6 (Monday March 31), with respect to synoptic-scale features.
Divergence in solutions increases thereafter, particularly with the strength/progression of the next trough moving across the western
CONUS and into the Plains. As such, no risk areas will be
considered beyond Day 6/Monday.

Day 4/Saturday, a couple of small-scale vorticity maxima/short-wave
troughs are forecast to cross the central portion of the country,
ahead of the stronger system advancing across the West. This
feature is forecast to reach the High Plains overnight, as a surface
low moves across the Kansas/Oklahoma vicinity. Models continue to
indicate that capping will remain an issue, hindering convective
development in the warm sector ahead of the low (across the Kansas/Oklahoma/western Missouri/western Arkansas area) at least
until after dark/overnight. While some severe threat may evolve
with storms which should be slightly elevated for the most part,
risk does not appear sufficient to warrant inclusion of a 15% risk
area.

Day 5/Sunday, more substantial cyclogenesis is expected, though
differences exist between the models in terms of timing/location of
the developing low -- and associated cold front. Nonetheless,
substantial warm-sector destabilization is forecast to occur from Missouri/Arkansas/eastern Texas eastward across the Mississippi
Valley during the day, and extending eastward across the
Midwest/Ohio and Tennessee Valleys. This will support scattered
thunderstorm development, within an increasingly sheared
environment. By early afternoon, severe/supercell storms are
expected, accompanied by the risk for very large hail, damaging
winds, and a few tornadoes. Storms should spread southeast of the
Ohio and Mississippi Valleys overnight, accompanied by ongoing
severe risk.

Day 6/Monday, risk will likely have shifted to near and east of the Appalachians, and southward to the Gulf Coast area, as the surface
cold front advances. Destabilization ahead of the front will
support continuation of severe risk given favorably strong flow
aloft, with storms reaching/moving off the Gulf and Atlantic Coasts
late in the period.

..Goss.. 03/26/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 270859
SWOD48
SPC AC 270857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Thu Mar 27 2025

Valid 301200Z - 041200Z

...DISCUSSION...
Predictability remains a concern during the medium-range period.
Models reveal notable differences even in the Day 4-5 time frame
with respect to strength of the eastern U.S. upper trough, and
associated evolution/development of the surface pattern. As the
initial surface system moves offshore late in the Day 5 period
(Tuesday morning), substantial divergence in solutions is evident
with the next trough moving into/across the western CONUS. Given
these differences, any severe potential beyond Day 5 cannot be
quantified with any degree of confidence.

With that said, a fairly widespread area of severe potential remains
evident Day 4/Sunday, ahead of a cold front moving eastward across
the Mississippi and Ohio and eventually the Tennessee Valleys.
Northward advection of 60s dewpoints is expected ahead of this
front, which will combine with daytime heating to boost mixed-layer
CAPE into the 1000 to 1500 J/kg range, and potentially above 2000
J/kg farther southwestward along the front from East Texas into the
lower Mississippi Valley.

As a belt of strong southwesterly flow aloft overspreads the moistening/destabilizing pre-frontal boundary layer, development of strong/severe storms is expected near and ahead of the boundary
during the afternoon -- potentially extending as far southwestward
as East Texas. Along with potential for large hail and damaging
winds, likelihood for supercell storms suggests potential for a few
tornadoes as well. Risk will spread eastward through the evening
across portions of the Midwest/Ohio Valley and Mid/Lower Mississippi
Valley, and southeastward into the Tennessee Valley and central Gulf
Coast states overnight -- likely persisting through the end of the
period.

Day 5/Monday, models begin to differ more substantially with respect
to surface frontal location -- particularly with northern extent.
The GFS depicts the front as extending from New England
southwestward to the Texas Coast Monday morning, while the ECMWF
places it from Lower Michigan to coastal Texas. By late afternoon,
the GFS shows the front reaching the New England coastal area and
Mid-Atlantic region, focusing the primary severe threat from the
Mid-Atlantic area southwestward. Meanwhile, some risk could extend
as far north as the Lower Great Lakes region/central Appalachians
per the ECMWF's deterministic forecast. At this time, will keep the
Day 5 risk area focused from the Mid-Atlantic region to the lower
Mississippi Valley, though adjustments/refinements to the area over
the next several days will likely be required.

..Goss.. 03/27/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 280902
SWOD48
SPC AC 280900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Fri Mar 28 2025

Valid 311200Z - 051200Z

...DISCUSSION...
Widespread storms and at least some attendant severe risk will be
ongoing at the start of the Day 4 period (Monday March 31) -- with
the band of convection likely extending along the west slopes of the Appalachians initially. Diurnal destabilization along and east of
the mountains remains a question, particularly with northward extent
into the Northeast, and thus the northern periphery of the risk area
remains in question -- in what will likely be a very low CAPE/high
shear environment -- suggestive of damaging gusts being the primary
concern over northern portions of the area.

Farther south, greater CAPE is expected, particularly from the
Carolinas into the central Gulf Coast states. Here, an all-hazards
risk is forecast to continue from the Day 3 period into Day 4.
Storms/severe risk will shift eastward with time, crossing the East
Coast states through the afternoon and evening, before clearing the
coast overnight.

Day 5/Tuesday looks to be a relative down day in terms of severe
potential, with moisture beginning to return northward into the
central U.S. ahead of the next system.

Day 6/Wednesday, moisture will continue returning northward across
the central U.S., though substantial differences in timing/evolution
of the upper system exists between the (slower) ECMWF and (faster)
GFS. However, the GEFS ensemble mean is slower than the operational
GFS, not quite as slow as but more in line with the ECMWF -- and the
Euro ensemble mean. Given this, confidence is high enough to
proceed with introduction of a broad -- though areally uncertain --
15% area. This system would appear to have the potential to produce
another fairly widespread/all-hazards severe event, but will likely
require a good bit of adjustment over the next few days.

Beyond Day 6, confidence in evolution of the large-scale features
diminishes further, due to the aforementioned differences between
operations runs of the global models. As such, no areas will be
delineated beyond Day 6.

..Goss.. 03/28/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 280910
SWOD48
SPC AC 280909

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0409 AM CDT Fri Mar 28 2025

Valid 311200Z - 051200Z

CORRECTED GRAPHIC

...DISCUSSION...
Widespread storms and at least some attendant severe risk will be
ongoing at the start of the Day 4 period (Monday March 31) -- with
the band of convection likely extending along the west slopes of the Appalachians initially. Diurnal destabilization along and east of
the mountains remains a question, particularly with northward extent
into the Northeast, and thus the northern periphery of the risk area
remains in question -- in what will likely be a very low CAPE/high
shear environment -- suggestive of damaging gusts being the primary
concern over northern portions of the area.

Farther south, greater CAPE is expected, particularly from the
Carolinas into the central Gulf Coast states. Here, an all-hazards
risk is forecast to continue from the Day 3 period into Day 4.
Storms/severe risk will shift eastward with time, crossing the East
Coast states through the afternoon and evening, before clearing the
coast overnight.

Day 5/Tuesday looks to be a relative down day in terms of severe
potential, with moisture beginning to return northward into the
central U.S. ahead of the next system.

Day 6/Wednesday, moisture will continue returning northward across
the central U.S., though substantial differences in timing/evolution
of the upper system exists between the (slower) ECMWF and (faster)
GFS. However, the GEFS ensemble mean is slower than the operational
GFS, not quite as slow as but more in line with the ECMWF -- and the
Euro ensemble mean. Given this, confidence is high enough to
proceed with introduction of a broad -- though areally uncertain --
15% area. This system would appear to have the potential to produce
another fairly widespread/all-hazards severe event, but will likely
require a good bit of adjustment over the next few days.

Beyond Day 6, confidence in evolution of the large-scale features
diminishes further, due to the aforementioned differences between
operations runs of the global models. As such, no areas will be
delineated beyond Day 6.

..Goss.. 03/28/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 290903
SWOD48
SPC AC 290902

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0402 AM CDT Sat Mar 29 2025

Valid 011200Z - 061200Z

...DISCUSSION...
Medium-range models appear to be in fairly good agreement through
much of the medium-range period, with respect to large-scale pattern evolution/placement of the main synoptic-scale features. One
primary difference between the GFS and ECMWF at this time is that
the EC is more highly amplified with the upper pattern through the
period, and thus -- in general -- depicting stronger surface
features and greater flow aloft/wind shear.

One result of the higher amplitude of the ECMWF manifests Day
4/Tuesday April 1. As the eastern U.S. trough moves off the
Atlantic Coast, and the cold front stalls over the northern Gulf of
America early, northward return of this boundary as a warm front is
forecast over the southern and eventually the central Plains.
Central High Plains cyclogenesis is expected along this front as it
shifts northward. However, given the more amplified nature of
western troughing within the ECMWF, a much stronger surface cyclone
is progged by the EC as compared to the GFS (984 mb vs. 991 mb
respectively). The result is much stronger low-level theta-e
advection across the central/southern Plains depicted by the EC,
driving a much more rapid northward advance of the warm front. Both
models suggest after-dark convective development, but where the GFS
depicts weaker, elevated CAPE across Kansas, the EC's more robust,
potentially near surface-based CAPE suggests greater, more
widespread severe potential than the GFS. At this time, a small 15%
area will be introduced, centered over the mid Missouri Valley area,
mainly for the potential for hail with stronger storms. Later
refinements of the risk area will likely be required.

Day 5/Wednesday, a widespread, potentially substantial severe event
remains apparent, and with greater agreement within the models with
respect to the upper trough advance and associated positioning of
the surface low/cold front, greater confidence with respect to the
degree of risk exists. While a very similar 15% risk area will be
depicted as in yesterday's outlook, a 30% area is being introduced
from Arkansas northeastward to the mid Ohio Valley. It appears that
the environment will become conducive for supercells, with very
large hail, damaging winds, and strong tornadoes all possible during
the afternoon and evening hours.

From Day 6 onward, the cold front will continue its eastward advance
across the Ohio Valley and into/across the Northeast/New England.
However, much slower southward progression of the cold front is
expected, with an eventual drift northward as a warm front that then lingers/oscillates across the Ohio Valley/Mid South/central and
southern Plains through the end of the period. This will occur as
a slow-moving trough moves into the West, and eventually evolves
into a cut-off low. While weak disturbances eject eastward through southwesterly flow aloft across the central U.S. -- each of which
may bring rounds of convection/severe potential in the day 6-8 time
frame, narrowing down specific/greater areas of potential is
difficult at this time.

..Goss.. 03/29/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 300901
SWOD48
SPC AC 300859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Sun Mar 30 2025

Valid 021200Z - 071200Z

...SEVERE WEATHER OUTBREAK POSSIBLE ON D4/WED...

...DISCUSSION...
Medium-range models appear to be in good agreement with overall
evolution of the synoptic-scale pattern into the Day 7 (Saturday
April 5) time period, when divergence in solutions increases.

Earlier in the period however, model consistency lends fairly high
confidence that a widespread/potentially substantial outbreak of
severe weather will evolve Wednesday/Day 4, from Lower Michigan and
the Ohio Valley, southwestward across the Middle and Lower
Mississippi Valleys, and into eastern portions of Texas and
Oklahoma. Convection will likely be ongoing or developing early in
the day, over western portions of the risk area -- from Wisconsin
southwestward to Oklahoma/North Texas. As an upper low shifts
northeastward across the northern Plains toward the upper
Mississippi Valley through the day, and the cold front crosses Iowa/Missouri/eastern Oklahoma, steep lapse rates atop a
moist/diurnally heating warm sector will support widespread
convective development.

With ascent along the front somewhat modest as stronger large-scale
ascent focuses northward into the western Upper Great Lakes and into
Ontario, storm mode may tend toward isolated storms, as opposed to
more linear development. This, combined with flow that is forecast
to weakly veer but dramatically strengthen with height, suggests a
primarily supercell storm mode. In additional to very large hail
(particularly with southward extent), widespread damaging winds and
several tornadoes are expected, some possibly significant. Risk is
expected to continue well into the evening and likely overnight,
shifting slowly eastward across the Midwest and mid/lower
Mississippi Valley through the end of the period.

Day 5/Thursday, trailing portions of the cold front should become
aligned east-northeast to west-southwest across the Ohio and mid
Mississippi Valleys and into the southern Plains, as the upper
system shifts quickly across eastern Canada. While weak short-wave
ridging will evolve atop the surface frontal zone in the wake of the
departing system, daytime heating of a very moist boundary layer
along and south of the front combined with strong flow aloft will
support reinvigorated convection through the afternoon and evening
hours, along with attendant severe-weather risk.

Day 6/Friday, the surface front should remain quasi-stationary, but
short-wave ridging should increase as a cut-off low evolves across
the West. As such, much of the Day 6 convection may occur to the
cool side of the surface front, in the zone of warm
advection/isentropic ascent. While some severe risk will likely
evolve, mainly in the form of hail, uncertainty overall (given the
ridging aloft) precludes inclusion of a Day 6 risk area.

By the weekend, deviation in model solutions increases, due to
uncertain evolution of the low/trough over the West. As such, no
risk areas will be included.

..Goss.. 03/30/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 310900
SWOD48
SPC AC 310859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon Mar 31 2025

Valid 031200Z - 081200Z

...DISCUSSION...
Active and progressive mid-level flow will persist across the CONUS
as a large upper trough moves from the Great Lakes into eastern
Canada. Several additional troughs, embedded within strong
west/southwesterly flow aloft, will move over the lower 48 through
the next week. Deep moisture and strong mid-level flow overlapping
will favor severe potential across the southern Plains, Mid MS/OH
Valleys and the Eastern CONUS through the extended forecast period.

...D4/Thursday...
As the primary upper trough departs to the northeast, the cold front
will stall across the OH/MS Valleys and into the southern Plains. A
secondary trough embedded within the southwesterly flow will emerge
over the southern Rockies and lift over the southern/central Plains.
A surface low, with trailing dryline and the stationary front, will
focus convective development through the afternoon and evening. The
broad warm sector, ample moisture, and steep mid-level lapse rates
will support moderate to strong instability, overlapping with robust
deep-layer shear. Severe thunderstorms appear likely from Northeast
TX, through AR/LA and into the Mid MS/OH Valleys.

Additionally, some severe risk may develop over parts of the Mid
Atlantic as the cold front slowly approaches from the northwest.
Relatively strong flow aloft may overlap with an increasingly moist
airmass, supporting some potential for storms with a wind/hail risk.
However, weak shortwave ridging, and multiple preceding days of
thunderstorm potential casts considerable uncertainty on the
potential for storms and the positioning of the front/quality of the
low-level airmass.

...D5/Friday...
The upper-level pattern begins to change D5/Friday as an upper low
is forecast to emerge across parts of the Southern Plains and
northern Mexico. Deep meridional flow will overspread parts of TX,
OK and AR while the front begins to sag south across the MS and OH
Valleys. Some supercell risk may develop across the Red River
vicinity and across the mid MS Valley near the stalled front.
However, the surface picture remains very complicated due to
multiple preceding days of convective potential.

...D6/Saturday and beyond...
Confidence in the upper-level evolution diminishes D6/Saturday and
through the weekend, as the projected upper low begins moving
eastward. Increasing high pressure over the northern US may begin to
suppress the northward extent of the deeper surface moisture. While
some severe risk may exist given relatively strong mid-level flow
near the stalled front from the ArkLaTex eastward into the
Southeast, model solutions vary greatly on the affected area and
associated hazards. Confidence is too low to initiate severe
probabilities.

..Lyons/Goss.. 03/31/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 010859
SWOD48
SPC AC 010857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Tue Apr 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
Amplified mid-level flow and deep moisture south of a quasi
stationary frontal zone will persist over much of the central and
eastern CONUS through the first half of the extended forecast
period. Models are in generally good agreement with the progression
of the pattern and the potential for severe storms. However, some
key differences, and days of preceding convection will modulate
potential in the coming days.

...Day4/Friday...
The broad upper trough over the western US is forecast to gradually
deepen Friday into the weekend, as an upper low forms over northern
Mexico. Flow aloft will become increasingly southerly over the
southern Plains while it curves anticyclonically over the Mid South
and eastern US. A rich pool of deep moisture will continue to reside
along a quasi stationary frontal zone from the Red River to the OH
Valley. Several clusters of strong to severe storms appear possible
within the broadly favorable zone of weak ascent and large
buoyancy/shear. The surface picture remains very complicated due to
multiple preceding days of convective potential.

...Day5/Saturday...
The primary mid-level impulse will begin to eject across northern
Mexico, eventually reaching the lower/middle MS Valley D5/Saturday.
Model differences begin to emerge on the latitudinal extent of the
warm sector owing to differences in the timing/structure of the
ejecting upper cyclone. Regardless, continued southerly low-level
flow will replenish deep moisture over much of the ArkLaTex and
Southeastern US. A surface low and cold front will gradually
intensify across the Mid South, likely focusing severe potential
ahead of it. The intensity of the severe risk will likely be tied to
ongoing storms from the prior Day 4, but supercells are possible
from east TX into the MS Valley and parts of the Southeast into
Saturday night.

...Day6-8...
The cold front and low will continue to move eastward with the upper
trough through the end of the weekend and into early next week. Some
severe risk could emerge over parts of the Southeast/eastern US with
seasonably high moisture and instability. However, model differences
on the frontal timing and the potential for multiple rounds of
proceeding convection make severe potential very uncertain beyond
Day 5.

..Lyons.. 04/01/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 020902
SWOD48
SPC AC 020900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Wed Apr 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
The mid-level flow pattern will undergo significant amplification
over the next several days as a large western US trough begins to
move eastward. Very rich moisture will support widespread
thunderstorm potential across parts of the Southeast and eastern US
through the weekend.

...D4/Saturday Mid South...
The upper low over northern Mexico will continue to amplify as it
begins ejecting eastward across the lower and mid MS Valley. A
strong 100+ kt jet will move east of the trough and overspread a
relatively broad warm sector across the Sabine and MS Valleys into
parts of TN/KY. Unseasonably rich moisture from several days of
southerly flow will be in place ahead of a surface low and cold
front. One or more rounds of severe storms, including supercells,
appears likely from eastern TX into AR, LA, and MS through the day.
All hazards will be possible. Storms should eventually grow upscale
into a line or cluster and spread eastward overnight into parts of
AL, FL, and GA.

The northern bound of the risk area across the TN Valley and into
the OH valley appears somewhat conditional. Multiple preceding days
of storms may limit the northern extent of the deeper moisture and
buoyancy. However, some severe risk likely exists given the
intensity of the low-level jet and abundance of moisture.

...Day 5...
The severe threat is likely to carry over from Day 4 in the form of
a squall line, as the upper wave gradually devolves into a broader positive-tilt trough. Strong mid-level flow and ascent will persist
over a broadening warm sector across the Southeast. While lapse
rates appear weak from several days of convection, some severe risk
is possible. The intensity of the severe risk will be heavily
dependent on the convective evolution from the prior day 4 which is
very unclear at the moment. Will add a 15% area across parts of AL,
FL, GA and SC where the best overlap of mid-level flow and robust
moisture are expected to support potential for damaging gusts.

A severe risk may also develop across parts of the Carolinas and mid
Atlantic Day5/Sunday. As the upper wave lifts to the north, ascent
will overspread returning surface moisture as far north as southern
PA. It is unclear how much buoyancy will be present with the
potential for widespread clouds. However, strong flow fields will be
available to any convection that can develop.

...D6+...
Offshore flow and high pressure will begin to dominate the extended
period as mid-level ridging intensifies over the center of the
country. Much cooler and stable conditions behind the advancing cold
front appear likely to temporarily end broader potential for severe
storms through early next week.

..Lyons.. 04/02/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 030824
SWOD48
SPC AC 030822

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CDT Thu Apr 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
Models are in relatively good agreement for the Sunday/D4 to
Monday/D5 period, depicting an elongating upper trough sweeping east
from the OH/TN Valleys to the East Coast.

On Sunday/D4, a leading midlevel wave is forecast to move out of AR
and across TN/KY, with little amplitude and poor lapse rates by this
time. An extensive area of rain and thunderstorms will be ongoing
along the length of the cold front throughout the day, from the
Northeast to the northern Gulf Coast. Some severe wind threat is
expected, mainly over parts of the Southeast where dewpoints will be
higher and as deep-layer shear remains favorable.

The trend of widespread precipitation along this front will continue
into early Monday/D5, from the Carolinas into FL. The severe risk
should continue to dwindle as large-scale support weakens, but
low-end potential cannot be ruled out over these areas.

For the Tuesday/D6 to Thursday/D8 time frame, the weather pattern
will be much less conducive to severe storms, with a ridge building
over the West, and northwest flow across the central states.
Periodic surges of high pressure are forecast, helping to keep
conditions mostly stable over the bulk of the CONUS.

..Jewell.. 04/03/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 040823
SWOD48
SPC AC 040822

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CDT Fri Apr 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
...Monday/Day 4 and Tuesday/Day 5...
On Monday, a cold front is forecast to move southeastward across the
eastern Carolinas, southeast Georgia and Florida. It appears that
pockets of moderate instability will be possible ahead of the front
by midday. Considering that strong deep-layer shear is forecast
across much of the Southeast, thunderstorms that form near the front
could develop an isolated severe threat. Severe wind gusts would be
possible near the leading edge of a convective line. However, the
timing of the cold front as it passes through the Southeast remains questionable, and uncertainty exists concerning instability,
suggesting predictability is low for Monday.

On Tuesday, surface high pressure is forecast to move across the
central and eastern U.S. Relatively dry and stable air should limit
any severe potential across the continental U.S Tuesday.

...Wednesday/Day 6 to Friday/Day 8...
From Wednesday to Friday, a cold front and an associated mid-level
trough is forecast to move southeastward across the central and
eastern U.S. Thunderstorm development will be possible ahead of the
trough near the front, beginning Wednesday night in the central
Plains. The most reliable model forecasts suggest that the most
likely area for an isolated severe threat on Thursday would be from
the central Plains into the mid Mississippi Valley. The severe
potential is forecast to shift eastward into the Carolinas on
Friday. Severe wind gusts and hail would be the primary threats.
During the mid to late week, instability is forecast to remain
relatively weak ahead of the front. Also, the timing of the trough
is still in question. This suggest that predictability is low from
Wednesday to Friday.

..Broyles.. 04/04/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 050849
SWOD48
SPC AC 050848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sat Apr 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
A mid-level trough is forecast to move across the Atlantic Coastal
states on Tuesday, as a dry airmass moves across the eastern and
southern U.S. From Wednesday to Friday, a mid-level trough is
forecast move southeastward from the central states into the eastern
U.S., becoming increasingly amplified with time. Ahead of this
feature, instability is forecast to remain weak. Isolated severe
storms would be possible ahead of the trough in the lower Missouri
and mid Mississippi Valleys Wednesday night. The severe threat is
forecast to shift eastward into the Ohio and Tennessee Valleys on
Thursday, and to the Carolinas on Friday. One of these days could be
a potentially more active severe weather day, but predictability
remains low concerning trough timing, magnitude of instability and
convective mode. In the Great Plains from Friday into Saturday,
model forecasts suggest a moist airmass will advect northward across
the southern and central Plains. At mid-levels, a ridge is forecast
to move eastward across the central U.S. from Friday into Saturday.
Isolated severe storms that develop in the vicinity of the ridge
should be marginalized due to a lack of large-scale ascent.

..Broyles.. 04/05/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 060853
SWOD48
SPC AC 060852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CDT Sun Apr 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
...Wednesday/Day 4 to Friday/Day 6...
During the mid to late week, a mid-level shortwave trough is
forecast to amplify and move southeastward from the north-central
states into the eastern U.S. Low-level moisture return ahead of the
trough is expected to be slow, which should result in only weak
instability ahead of the system. As the trough progresses
southeastward, isolated strong thunderstorms will be possible
Wednesday night in parts of the central Plains. On Thursday, an
isolated severe threat may develop in parts of the Ozarks and
Ark-La-Tex. By Friday, the system is forecast to be in the
Southeast, where isolated severe storms will be possible in parts of
Georgia and the Carolinas. Any severe threat that develops from
Wednesday to Friday is expected to be marginal, mainly due to issues
with poor moisture return and relatively weak instability.

...Saturday/Day 7 and Sunday/Day 8...
On Saturday, a mid-level ridge is forecast to move eastward across
the central U.S. Some low-level moisture is expected to return
northward into the Great Plains, where instability may become strong
enough for a severe threat. However, subsidence in the vicinity of
the ridge is expected to keep any threat that develops very
isolated.

On Sunday, model forecasts suggest that a long fetch of
west-northwest mid-level flow becomes established over much of the
U.S. Although isolated thunderstorms may form within a somewhat
moist airmass over parts of the south-central states Sunday
afternoon, large-scale ascent is forecast to remain weak. This,
combined with uncertainties at this extended range, suggest that
predictability is low.

..Broyles.. 04/06/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 070859
SWOD48
SPC AC 070857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Mon Apr 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
...Days 4-5/Thursday-Friday...
A positively tilted large-scale trough will move slowly
east-southeastward across the Mid MS and OH Valleys on Day
4/Thursday. Ahead of the trough, partially modified Gulf moisture
will be returning ahead of a related front moving across the Lower
MS Valley. Thunderstorms are expected ahead of the front across
parts of the OH/TN Valleys, where weak buoyancy and strong midlevel
westerly flow will support an isolated severe-storm risk. However,
the limited low-level moisture and weak/veered low-level flow should
limit storm intensity. By Day 5/Friday, the midlevel trough will
take on a neutral tilt as it moves slowly eastward and amplifies
across the Appalachians. Preceding the trough, strong
south-southwesterly midlevel flow will overspread the partially
modified Gulf air mass over the coastal Mid-Atlantic -- where
isolated severe storms will be possible ahead of a related surface
front. Similar to Day 4/Thursday, the overall threat appears too
marginal for severe probabilities at this time.

...Days 7-8/Sunday-Monday...
A midlevel trough and strong west-southwesterly flow will overspread
the northern/central Plains on Day 7/Sunday, and continue across the Midwest/Great Lakes on Day 8/Monday. In response, boundary-layer
moisture will return northward ahead of a related lee trough across
the southern and central Plains on Day 7/Sunday, though a strong EML
should limit thunderstorm potential. By Day 8/Monday, guidance
varies considerably on the evolution of the midlevel trough and
related warm sector, limiting confidence in overall severe-storm
potential.

..Weinman.. 04/07/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 080839
SWOD48
SPC AC 080837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Tue Apr 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
On Day 4/Friday, an amplified large-scale trough will move slowly
eastward across the Appalachians. Ahead of a related surface low in
the lee of the Appalachians, weakly modified boundary-layer moisture
will be in place across the coastal Mid-Atlantic states. While
instability will be marginal, owing to the limited moisture and poor
lapse rates, strong south-southwesterly midlevel flow may support a
couple strong storms during the afternoon. The overall severe threat
appears too marginal for severe probabilities at this time.

By Day 6/Sunday, a midlevel trough will advance eastward across the northern/central Plains, while an elongated downstream surface
trough (with embedded surface lows) promotes partially modified Gulf
moisture return across the southern/central Plains and MS Valley.
Despite multiple surface boundaries across the Plains, current
indications are that a strong EML and related capping atop the
limited boundary-layer moisture should inhibit surface-based
thunderstorm potential.

Thereafter, medium-range guidance varies considerably regarding the
timing and evolution of the aforementioned midlevel trough and
associated warm sector -- limiting confidence in severe-storm
potential for Days 7-8/Monday-Tuesday.

..Weinman.. 04/08/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 090839
SWOD48
SPC AC 090837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Wed Apr 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
From Day 5/Sunday through Day 6/Monday, a robust midlevel trough
will advance eastward from the northern Plains to the Great Lakes.
On Day 5/Sunday, a related broad/elongated surface low will move
eastward across the northern/central Plains, while a dryline
develops farther south over the southern Plains. Isolated strong
storms may be possible ahead of the surface low in the Upper MS
Valley, though poor boundary-layer moisture will tend to limit the
severe risk. Farther south along the dryline, a strong EML and
related capping should inhibit thunderstorm development, despite the development of larger buoyancy here.

On Day 6/Monday, a cold front will move across the eastern half of
the CONUS, in tandem with the eastward-moving trough. Strong
midlevel flow and a weakly unstable air mass along the front may
support a marginal severe-storm risk from the OH Valley
southwestward to the Ozarks. However, considerable differences among
the medium-range guidance regarding the quality of boundary-layer
moisture ahead of the front casts uncertainty on the overall risk.

..Weinman.. 04/09/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 100834
SWOD48
SPC AC 100833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Apr 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Primary feature of interest will be a shortwave trough over MT at
12Z Sunday and its major amplification into a broad eastern
CONUS/southeast Canadian trough through mid-week. Poleward moisture
quality from the western Gulf will remain sub-optimal, but will
improve through D5/Monday. The northeast extent of weak surface
buoyancy should reach the OH Valley by Monday afternoon, where
guidance has been trending farther south with an intense mid-level
jet. Given a prior EML and the deep surface cyclone tracking over
Lake Superior to central ON vicinity, convective coverage may be
limited along the trailing cold front. Still, consensus of guidance
suggests that some fast-moving convection should accompany the
portion of the front in the OH Valley vicinity. Robust 700-500 mb
wind profiles should offer at least a threat for damaging winds.

Depending upon timing of frontal passage, a limited-area severe
threat may exist on D6/Tuesday along the Southeast Atlantic coast. A
compact southern-stream shortwave impulse, approaching the backside
of the broad east CONUS trough, indicates low-probability severe
potential over the southern Great Plains on D7/Wednesday into the
western Gulf Coast vicinity D8/Thursday.

..Grams.. 04/10/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 110832
SWOD48
SPC AC 110830

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CDT Fri Apr 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
...D4/Monday...
Further amplification of a broadening mid/upper-level trough and
attendant surface cyclone is expected across the Upper Great Lakes
to the southern ON/QC border area. Poleward moisture quality from
the western Gulf will remain sub-optimal, but will continue to
improve beneath a lobe of the southern Great Plains EML. The
northeast extent of weak surface buoyancy should overspread the OH
Valley by Monday afternoon. This portion of the front will coincide
with robust 700-500 mb southwesterlies, yielding potential for
fast-moving convection. Guidance consensus suggests this will remain
the favored corridor for at least a damaging wind threat.

...D7/Thursday...
Guidance has trended towards greater amplification of a Prairie
Provinces to north-central CONUS upper trough, although run-to-run
continuity is quite poor. This would be accompanied by a cold front
sweeping southeast into the South-Central States. With potentially
greater low-level moisture relative to the D3-4 system, some severe
potential may become evident once predictability improves.

..Grams.. 04/11/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 120843
SWOD48
SPC AC 120841

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CDT Sat Apr 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
After a relative lull in severe potential mid-week, latest guidance
indicates increasing severe possibilities late week. Compared to 24
hours ago, deterministic models have vastly changed to an evolution
of a shortwave trough digging south from the Canadian Rockies into
the Lower CO Valley during D5-7/Wednesday-Friday. This would support
a greater breadth and quality of western Gulf moisture advection
across the central states beneath an initially pronounced EML. SPC
and NSSL GEFS-based ML guidance indicate broadening 5 to mesoscale
pockets of 15 percent probabilities during D6-8/Thursday-Saturday.
But given the lack of day-to-day continuity and rather large spread
across ensemble guidance, consideration of any severe area appears
premature this cycle.

..Grams.. 04/12/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

ACUS48 KWNS 130853
SWOD48
SPC AC 130851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Sun Apr 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
An active severe weather pattern is expected late week into next
weekend.

...D5/Thursday...
Guidance has converged to a signal of severe-storm threat centered
on Thursday evening as a deep surface cyclone becomes established in
the KS vicinity, downstream of a longwave trough in the West. An
enriching low-level moisture plume will be advected nearly due north
from the western Gulf towards the Lower MO Valley. A stout EML
should limit convective development along much of the dryline. But a strengthening low-level jet should support thunderstorm development
to the northeast of the surface low amid strong deep-layer shear.

...D6/Friday...
A rather broad swath of 50+ kt 500-mb southwesterlies appears likely
to become established from the southern High Plains to the Great
Lakes, downstream of a broad trough in the Southwest and a separate northern-stream wave around northern ON. While the deep cyclone over
the KS vicinity will weaken, it should track towards the central
Great Lakes in response to the northern wave. Along its trailing
cold front, extensive thunderstorm development is anticipated Friday afternoon/evening. Given the aforementioned strong mid-level flow
regime, a broad corridor of severe threat is warranted.

...D7-8/Saturday-Sunday...
Predictability for a 15 percent highlight wanes somewhat next
weekend, but areas will probably be needed in later outlooks.
Saturday may consist of confined, bimodal threat areas across the
Lower Mid-Atlantic States and southern High/Great Plains. For the
former, the degree of instability and position of a southeast-moving
cold front on the periphery of a fast zonal flow regime are the main uncertainty drivers. For the latter, timing of the pivot and
eastward ejection of the Lower CO Valley shortwave impulse into the south-central states will be critical. Based on latest guidance, it
appears Sunday could have a broader corridor of severe potential.

..Grams.. 04/13/2025

= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.20-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)