ACUS02 KWNS 280703
SWODY2
SPC AC 280702

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0102 AM CST Sat Dec 28 2024

Valid 291200Z - 301200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE SOUTHEAST AND MID-ATLANTIC STATES...

...SUMMARY...
Severe storms are possible across parts of the Southeast,
Mid-Atlantic, and upper Ohio Valley on Sunday.

...Synopsis...
A pronounced upper-level trough will intensify as it pivots
northeast across much of the eastern U.S. Sunday. An associated
surface low will deepen as it moves northeast from western portions
of KY/TN into the eastern Great Lakes region. A trailing cold front
will move east across the southeast/mid-Atlantic states, approaching
the coast during the afternoon/evening.

...Southeast/mid-Atlantic States...
One or more lines of thunderstorms will likely be ongoing at 12z
Sunday near and in advance of the cold front, aided by large-scale
ascent with the upper trough and low-level warm/moist advection.
These early-day storms will have severe potential, primarily in the
form of strong/damaging gusts. Low-level moisture, with surface dew
points in the 60s, will advect north throughout the day, reaching as
far north as the VA/NC border by afternoon. Extensive cloud cover
will tend to temper heating/destabilization, with generally weak
instability in advance of the cold front (pockets of MLCAPE between
500 and 1000 J/kg, locally higher over the northern FL peninsula).

Thunderstorms should re-intensify or re-develop during the afternoon
as the stronger large-scale ascent overspreads the moistening warm
sector, with a linear structure likely the dominant storm mode along
the cold front as it moves towards the coast by late
afternoon/evening. Very strong low- and mid-level wind fields will
aid in downward momentum transport resulting in damaging winds as
the primary severe risk. Transient QLCS circulations will also pose
a risk for a tornado or two, especially from portions of eastern GA
across the central Carolinas, where the best overlap of instability
and favorable low-level shear will exist. Isolated instances of hail
will also be possible with the most intense updrafts.

...Upper Ohio Valley...
Beneath the primary mid-level cold core near the center of the
surface low, differential temperature advection above low-mid 50s F
dewpoints should steepen low/mid-level lapse rates sufficiently for
modest diurnal destabilization resulting in a few hundred J/kg of
MUCAPE. This may be sufficient for a risk of a few damaging wind
gusts or small hail with low-topped strong storms, given 45-60 kt of
low-level flow beneath the upper trough.

..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