SPC Dec 29, 2024 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1020 AM CST Sun Dec 29 2024

Valid 291630Z - 301200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
OVER PARTS OF THE CENTRAL/EASTERN CAROLINAS...

...SUMMARY...
Sporadic damaging wind gusts are possible this afternoon over the
central and eastern Carolinas into southern Virginia.  More-isolated
severe storms may occur across parts of the central Appalachians and
Ohio Valley, and over southernmost Florida.

...Carolinas...
A large and negatively-tilted shortwave trough is rotating
northeastward across the TN/OH Valleys today, with intense low and
mid-level wind fields overspreading much of the eastern US.  A
pre-frontal squall line has advanced eastward into central NC and
eastern SC, well ahead of the primary surface cold front and
considerably faster than model guidance had predicted.  This line is
moving through weak instability, with very limited lightning being
observed.  Nevertheless, low-level winds and convergence along the
line are quite strong, leading to gusty and occasional damaging
winds.  This trend will continue through the afternoon across the
eastern Carolinas.

...NC/VA This Evening...
Behind this line, widespread clouds and dewpoints in the 50s will
result in continued weak thermodynamic profiles for deep convection.
 However, given the large-scale ascent and strong winds aloft, there
remains some chance of re-development of showers and occasional
thunderstorms from central NC into VA this evening.  If this
scenario unfolds, isolated damaging wind gusts could occur.

...OH/PA...
A deep surface low currently over southern IN will track into
northwest OH today, with a occluded front extending eastward from
the low across OH.  Widespread cloud cover will limit CAPE to
100-200 J/kg this afternoon ahead of the front.  However, very
strong winds aloft and large scale forcing for ascent is expected to
result in scattered showers and thunderstorms.  This fast-moving
convection may result in locally damaging wind gusts or a brief
tornado as it affects much of OH and western PA through early
evening.

...FL Keys...
An east-west band of thunderstorms is sagging southward across the
FL Keys today.  Several areas of rotation have been noted all
morning along the line, which may pose a risk of gusty winds or
waterspout/brief tornado activity.

..Hart/Lyons.. 12/29/2024

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