592
ACUS03 KWNS 250728
SWODY3
SPC AC 250727

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Sat May 25 2024

Valid 271200Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS MONDAY ACROSS MUCH
OF SOUTH CENTRAL PENNSYLVANIA...THE EASTERN WEST VIRGINIA
PANHANDLE...MUCH OF MARYLAND...VIRGINIA AND NORTH
CAROLINA...SOUTHERN NEW JERSEY...DELAWARE...

...SUMMARY...
Severe thunderstorms may develop Monday afternoon, and overspread
much of the Mid Atlantic accompanied by a risk for damaging wind
gusts into Monday evening.

...Synopsis...
Models indicate that mid/upper flow will undergo amplification
across the northern mid-latitudes of the Pacific into North America
into and through this period.  Monday into Monday night, this is
forecast to include digging troughing offshore of the Pacific
Northwest coast, to the south of a broad low developing over the
northeastern Pacific, and downstream ridging building across and to
the east of the Canadian/northern U.S. Rockies.

Farther downstream, it appears that larger-scale troughing will
continue to evolve east of the upper Mississippi Valley into the
northern and middle Atlantic Seaboard.  One significant embedded
short wave may pivot north-northeast of Lake Huron and Georgian Bay,
accompanied by a relatively compact, but deep surface cyclone.  A
trailing perturbation is forecast to pivot eastward and
northeastward through the Ohio Valley and lower Great Lakes region,
with increasingly difluent and divergent upper flow likely
overspreading the Mid Atlantic region during the late afternoon and
evening.

While surface troughing deepens to the lee of the Blue Ridge during
the day in response to this forcing, a cold front trailing the
cyclone likely will advance toward the Appalachians, as well as into
the Gulf States, before progressing into the Atlantic Seaboard
Monday night.

...Mid Atlantic...
Remnants of a plume of elevated mixed-layer air may overspread the
southern through middle Atlantic Seaboard during the day, in advance
of the approaching short wave trough.  This may contribute to
moderately large CAPE exceeding 2000 J/kg, where surface dew points
remain in the mid 60s to near 70F within the deepening surface
troughing.  As a 50+ kt mid-level jet noses northeast of the
southern Appalachians, strengthening deep-layer shear and mean wind
fields will contribute to an environment potentially conducive to
organized severe thunderstorm development.

This could include a risk for supercells, at least initially, but
pre-frontal convection developing along or across the Appalachians
may evolve into an increasingly organized line while spreading east
of the Blue Ridge late Monday afternoon and evening.  As this
occurs, severe wind gusts will probably become the primary potential
hazard after initial, more discrete storms pose a risk for severe
hail, locally damaging wind gusts, and perhaps a risk for a tornado
or two.

..Kerr.. 05/25/2024

$$