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  • DAY2SVR: Day 2 Convective Outlook

    From COD Weather Processor @1:2320/107 to All on Sat Oct 10 05:35:16 2026
    ACUS02 KWNS 100535
    SWODY2
    SPC AC 100532

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1232 AM CDT Sat Oct 10 2026

    Valid 111200Z - 121200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
    NORTH CAROLINA...VIRGINIA...AND SOUTHEAST MARYLAND...

    ...SUMMARY...
    Widely scattered severe storms capable of a few tornadoes and
    damaging wind gusts appear possible over portions of North Carolina,
    Virginia, and southeast Maryland Sunday afternoon and evening. A
    brief tornado or two may occur over portions of the lower Colorado
    Valley Sunday morning, with sporadic occurrences of severe wind
    gusts possible into the Great Basin and central Rockies Sunday
    afternoon and evening.

    ...Synopsis...

    A mid/upper-level low over KY and TN Sunday morning is forecast to
    evolve into an open wave while progressing into the Mid-Atlantic by
    Sunday night. That system will be preceded by a focused corridor of
    height falls and a belt of 45-55+ kt southwesterly flow in the
    midlevels, which will overspread the Carolinas and southern
    Mid-Atlantic during the day. While the primary surface low will
    remain displaced to the northwest of the warm sector, secondary
    cyclogenesis is forecast during the afternoon over central VA at the
    junction of a cool front/trough advancing east from the Blue Ridge
    and a warm front lifting north into the Mid-Atlantic.

    Elsewhere, the remnants of Tropical Storm Rachel will weaken while
    accelerating from southern CA into the Great Basin within a belt of
    50-60 kt midlevel flow. The associated surface circulation/low will
    likewise develop from southern CA into northern UT by Sunday
    evening.


    ...Southern Mid-Atlantic into the Carolinas...

    A 40-45 kt low-level jet will persist over the Piedmont and Coastal
    Plain, enhancing the poleward transport of a moist boundary layer, characterized by dewpoints in the upper 60s to mid 70s. Showers and thunderstorms are likely to be ongoing at 12Z Sunday within the
    expanding warm sector with lingering clouds and areas of
    precipitation limiting daytime heating and resultant destabilization
    at many locations. Nonetheless, a moist and at least marginally
    unstable air mass will coincide with strengthening low-level and
    deep-layer shear, which may support transient supercells with the
    threat for a brief tornado or two and/or strong wind gusts spreading
    from the Carolinas into the southern Mid-Atlantic on Sunday.

    A higher-probability risk for sustained supercells capable of a few
    tornadoes and damaging winds may materialize by afternoon into
    evening from portions of central and eastern NC into south-central
    into southeast VA, where the 00Z REFS and HREF guidance indicates a
    corridor of locally stronger instability (SBCAPE up to 1000-1250
    J/kg). Those areas have been upgraded to 5% tornado and 15% wind
    probabilities and a related Level-2/Slight Risk.


    ...Lower Colorado Valley into the Great Basin and central Rockies...


    A low-level moisture plume (e.g., dewpoints in the mid 50s to
    mid-upper 60s) originating from the Gulf of CA will reside over the
    lower-CO Valley Sunday morning, with REFS and HREF guidance
    indicating SBCAPE of 500-1000 J/kg. Relatively strong vertical
    shear, aided by the low-level mass response to the remnant Rachel
    circulation, will be more than sufficient for supercells and bowing
    structures capable of isolated severe wind gusts and perhaps a brief
    tornado or two over the lower-CO Valley Sunday morning.

    As mentioned in the synopsis, the system will weaken through the
    day, leading to greater uncertainty in the extent of any associated
    severe weather threat during the afternoon into evening. That said,
    corridors of modest instability are expected to develop across
    portions of the Great Basin into the central Rockies, which combined
    with relatively strong cloud-bearing shear will be supportive of
    widely scattered severe storms capable of mainly severe wind gusts.

    ..Mead.. 10/10/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Oct 10 17:03:18 2026
    ACUS02 KWNS 101703
    SWODY2
    SPC AC 101701

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1201 PM CDT Sat Oct 10 2026

    Valid 111200Z - 121200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    VIRGINIA AND NORTH CAROLINA...

    ...SUMMARY...
    Isolated strong to severe thunderstorms capable of producing gusty
    winds and a tornado or two will be possible across parts of the
    Mid-Atlantic on Sunday. Additional strong storms are expected across
    parts of the Southwest and Great Basin.

    ...Carolinas to Mid-Atlantic...

    Strong deep-layer flow will overspread the region as the remnants of
    Isaias merge with upper troughing from the Ohio Valley to the
    Southeast. The surface low is expected to be over the central
    Appalachians Sunday morning, and will shift east/northeast across
    the Mid-Atlantic through early Monday. A surface front will extend
    south of the low and shift east across the region. Within the
    pre-frontal warm sector, a very moist airmass will be in place.
    Showers and cloudiness are expected across much of the area, and
    lapse rates will remain poor, limiting widespread stronger
    destabilization. However, a corridor of around 750-1000 J/kg MLCAPE
    may develop from eastern/central NC into VA, with more limited
    destabilization expected across the broader region.

    Given the strong flow field associated with the
    remnant/post-tropical system, transient supercell features could
    occur in one or more pre-frontal bands of convection. Isolated
    strong to severe gusts will be possible, along with a tornado or
    two.

    ...Southwest/Great Basin vicinity...

    Strong southwesterly flow aloft will overspread the Lower CO Valley
    to the Great Basin/central Rockies as an upper trough slowly digs
    and shifts east across the Pacific coast. The remnants of prior
    tropical storm Rachel will partially be responsible for enhancement
    of midlevel flow, and for modest boundary layer moisture across the
    Lower CO Valley. This system is expected to gradually weaken as it
    shifts northeast toward the Great Basin/central Rockies through the
    period.

    Pockets of modest destabilization amid favorable vertical shear will
    support bands of convection. Some transient supercell features will
    be possible. Given favorable shear and strong background flow, a few
    strong gusts and a tornado or two will be possible. The northeast
    extent of severe potential remains somewhat uncertain. Instability
    will wane with northward extent, but strong deep-layer flow may
    continue to support gusty winds with convective showers and isolated thunderstorms into parts of UT and western CO.

    ..Leitman.. 10/10/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Oct 11 04:57:30 2026
    ACUS02 KWNS 110457
    SWODY2
    SPC AC 110455

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1155 PM CDT Sat Oct 10 2026

    Valid 121200Z - 131200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    No severe weather is expected Monday through Monday night.

    ...Synopsis...

    An upper low initially over the Columbia Basin will develop south to
    the Sierra Nevada, while an embedded vorticity maximum progresses
    through the basal portion that feature from central/southern CA
    through the lower-CO Valley into the Great Basin. Downstream from
    those developments, a low-amplitude short-wave trough is forecast to
    translate from the northern or central High Plains into the upper
    Midwest and neighboring Upper Great Lakes regions by Monday night.
    At the surface, an area of low pressure initially over central NE
    will develop along a boundary into southern MN by late afternoon or
    early evening before reaching central WI Monday night.


    ...Upper Midwest...

    A plume of steep midlevel lapse rates will overspread the region on
    Monday, atop a moistening boundary layer, yielding a moderately
    unstable but capped air mass by afternoon along and south of the
    surface boundary and approaching cyclone. Elevated thunderstorms are
    expected to develop to the north of the surface warm sector over the
    northern Plains Monday morning within a zone of forcing for ascent
    preceding the short-wave trough. That convective regime is expected
    to spread into portions of MN and WI late Monday afternoon into
    night, amidst a thermodynamic environment featuring MUCAPE generally
    less than 1000 J/kg. While a few instances of hail approaching one
    inch appear possible, larger sizes are expected to be limited by the
    marginal instability and generally less than 30-35 kt of effective
    bulk shear.


    ...Lower Colorado Valley into the Great Basin...

    Increased forcing for ascent ahead of the vorticity maximum is
    expected to foster an areal increase in low-topped thunderstorms
    Monday afternoon, which are likely to continue into Monday night.
    Generally weak instability should limit severe weather potential;
    however, in areas where low-level lapse rates can sufficiently
    steepen, the downward transfer of stronger winds aloft could yield a
    few gusts approaching 58 mph. Some small hail may also accompany the
    strongest updrafts.

    ..Mead.. 10/11/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Oct 11 17:05:54 2026
    ACUS02 KWNS 111705
    SWODY2
    SPC AC 111703

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1203 PM CDT Sun Oct 11 2026

    Valid 121200Z - 131200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    No severe weather is expected Monday through Monday night.

    ...Upper Midwest/Great Lakes...

    An upper shortwave trough will develop northeast from the central
    High Plains to the Great Lakes on Monday. This will bring a belt of
    mildly enhanced westerly mid/upper flow across the region, with an
    increasing southwesterly low-level jet expected by Monday evening
    from the Mid-MS Valley into MI. At the surface, low pressure will
    shift east across MN/WI/MI, with a trailing cold front surging
    east/southeast across the central Plains and Upper Midwest. A warm
    front will be oriented west to east across northern WI to northern
    Lower MI. Elevated thunderstorms may develop by 00z near and north
    of this boundary on the edge of the increasing low-level jet and
    stronger warm advection ahead of the surface low/cold front. Cooling
    aloft will result in a plume of steep midlevel lapse rates
    supporting modest elevated instability. Small hail may occur with
    stronger updrafts within the modestly sheared environment across
    northern WI/the U.P. of MI and portions of northern Lower MI during
    the evening and overnight hours. Overall severe potential is
    expected to remain limited by modest instability and capping across
    the warm sector, precluding severe probabilities.

    ...Southwest/Great Basin...

    Lingering moisture across the Southwest and Great Basin will support
    scattered showers and thunderstorms within enhanced deep-layer
    southwesterly flow ahead of an approaching upper low and attendant
    trough. Meager destabilization will limit severe potential, though
    some gusty winds are possible given stronger synoptic flow.

    ...Southern High Plains...

    A few thunderstorms will be possible along a surface trough/dryline
    across western TX/eastern NM as low-level moisture returns north and
    west across the southern Plains. Modest vertical shear and weak
    instability should limit severe potential, though some locally gusty
    outflow winds are possible given steepened low-level lapse rates due
    to daytime heating into the upper 80s/low 90s.

    ..Leitman.. 10/11/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)