• DAY2SVR: Nws Storm Predic

    From Mike Powell@454:3/105 to All on Fri Dec 12 09:31:43 2025
    ACUS02 KWNS 120601
    SWODY2
    SPC AC 120559

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1159 PM CST Thu Dec 11 2025

    Valid 131200Z - 141200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Isolated weak thunderstorm activity is possible across South Florida
    and the Keys Saturday afternoon into Saturday night.

    ...Synopsis...
    The large-scale pattern on Saturday will feature a ridge across the
    western CONUS with troughing across the east. This mid-level trough
    will amplify on Saturday as a strong mid-level jet streak moves from
    the northern Plains to the Midwest. At the surface, a cold front
    will sharpen from the Ohio Valley to the Plains and move south
    rapidly Saturday evening.

    ...South Florida...
    Tropical moisture will start to advect northward across the southern
    Florida Peninsula on Friday. If this advects far enough north during
    the day, a few thunderstorms may be possible on the eastern sea
    breeze. During the overnight period, storm chances will increase
    across the western Florida Peninsula as a mid-level shortwave trough
    traverses the Gulf. Limited instability should preclude any severe
    weather threat from this activity.

    Shallow convection may develop along the southward moving cold front
    from southeast Texas to central Alabama late Saturday night, but
    warm temperatures aloft should limit lightning potential.

    ..Bentley.. 12/12/2025

    $$
    --- SBBSecho 3.28-Linux
    * Origin: ILink: CCO - capitolcityonline.net (454:3/105)
  • From Mike Powell@454:3/105 to All on Wed Nov 26 09:27:57 2025
    ACUS02 KWNS 260533
    SWODY2
    SPC AC 260531

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1131 PM CST Tue Nov 25 2025

    Valid 271200Z - 281200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Isolated thunderstorms are possible across southeast Florida on
    Thursday. Severe storms are not expected.

    ...Synopsis...
    A broad mid-level trough will deepen across the eastern CONUS,
    ushering in surface high pressure and associated cool and stable air
    across most of the CONUS, limiting thunderstorms over most locales
    tomorrow (Thursday). The one exception will be the southern FL
    Peninsula tomorrow afternoon and evening. Here, a surface cold front
    will sweep across the region, lifting a moist and buoyant low-level
    airmass before moving offshore. Isolated thunderstorms are possible
    during the afternoon hours, before the cold front clears moisture
    from the region.

    ..Squitieri.. 11/26/2025

    $$
    --- SBBSecho 3.28-Linux
    * Origin: ILink: CCO - capitolcityonline.net (454:3/105)
  • From Mike Powell@454:3/105 to All on Sat Dec 27 10:06:42 2025
    ACUS02 KWNS 270639
    SWODY2
    SPC AC 270637

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1237 AM CST Sat Dec 27 2025

    Valid 281200Z - 291200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN MO/AR TO THE
    OH AND TN VALLEYS...

    ...SUMMARY...
    A low-probability severe thunderstorm threat is forecast from Sunday
    afternoon into Sunday night from Missouri-Arkansas into the Ohio and
    Tennessee Valleys.

    ...MO/AR to the OH/TN Valleys...
    Phasing of multiple shortwave impulses will support amplification of
    an upper trough, mainly on Sunday night, as it progresses from the
    High Plains to the Great Lakes. This will induce deepening of a
    surface cyclone from the Lower MO Valley towards Lake Huron.
    Attendant cold front will accelerate Sunday night as it quickly
    sweeps east into the Upper OH Valley and south into the northwest
    Gulf by 12Z Monday.

    Isolated to scattered elevated thunderstorms are most likely on
    Sunday morning across parts of the Mid-MS Valley to the southern
    Great Lakes within a strengthening low-level warm conveyor. It is
    plausible that a few updrafts might weakly rotate, but meager
    buoyancy atop the stable surface and cluster convective mode appears
    supportive of only small hail.

    Primary forecast challenge is the degree of surface-based
    destabilization by Sunday afternoon, which will largely influence
    tornado and severe thunderstorm wind potential. Latest guidance
    remains split into two paths. This evening's RRFS/RAP/HRRR/HRW-ARW
    suggest that a plume of meager buoyancy with MLCAPE up to 500 J/kg
    should become established ahead of a cold front across the Ozarks to
    a portion of the Mid-MS Valley near the surface cyclone by
    afternoon. Meanwhile the NAM and HRW-NSSL indicate little to no
    surface-based buoyancy in the warm-moist sector along the front.
    Guidance consensus does suggest at least a low-topped, thin QLCS
    should become established along the front from IL/IN towards AR by
    early evening.

    The progressive nature of the front along with the paucity of
    surface-based instability downstream renders large uncertainty in
    whether lightning-producing convection will be maintained Sunday
    night along the front. However, kinematic fields will become
    increasingly impressive, with strong gusts likely accompanying
    low-topped convection along the front. CAM consensus though is for
    convection to wane early morning Monday as instability remains
    negligible. As such, have maintained the prior level 1-MRGL risk for
    wind, with a subset of low tornado probabilities from MO to IN.

    ..Grams.. 12/27/2025

    $$
    --- SBBSecho 3.28-Linux
    * Origin: ILink: CCO - capitolcityonline.net (454:3/105)