SPC Dec 31, 2024 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1025 AM CST Tue Dec 31 2024

Valid 311630Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING FROM EASTERN KENTUCKY INTO THE MID ATLANTIC REGION....

...SUMMARY...
Damaging to isolated marginally severe gusts, isolated large hail,
and a brief tornado are possible today from the central Appalachians
to parts of the Mid-Atlantic.

...KY to the Mid Atlantic Region...
A potent, negatively-tilted shortwave trough will move from the
upper OH Valley into NY/PA today, with an associated 80-100 knot
mid-level speed max nosing across the Carolinas.  Strong large-scale
forcing and low-level warm advection is resulting in sufficient lift
for the development of multiple lines/clusters of low-topped
convection (some with lightning) across parts of OH/KY/TN/WV.  This
activity will move quickly eastward through the day across the
central Appalachians and into the Mid Atlantic region this
afternoon/evening.  

Forecast soundings show cold mid-level temperatures, resulting in
steep lapse rates aloft.  This will continue to support a threat of
thunderstorms through tonight.  Low-level moisture is quite limited,
and forecast CAPE values are below 500 J/kg.  Nevertheless,  low and
mid-level wind fields are very strong, which could easily mix down
within any more-organized convection.  Low-level shear is also
strong enough to support updraft rotation (as already noted in a few
cells this morning in KY) which could pose a risk of a brief tornado
or occasional hail through the period.

..Hart.. 12/31/2024

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