762
ACUS11 KWNS 301611
SWOMCD
SPC MCD 301611
MDZ000-DEZ000-VAZ000-NCZ000-DCZ000-WVZ000-301815-

Mesoscale Discussion 1489
NWS Storm Prediction Center Norman OK
1111 AM CDT Sun Jun 30 2024

Areas affected...Portions of central/eastern NC/VA...MD...and DE

Concerning...Severe potential...Severe Thunderstorm Watch likely

Valid 301611Z - 301815Z

Probability of Watch Issuance...80 percent

SUMMARY...Thunderstorms are expected to develop over the next couple
of hours, posing a risk for damaging wind gusts. A watch will likely
be needed for portions of the region withing the next 1-2 hours.

DISCUSSION...Portions of northern VA into MD/DE continue to
experience greater cloud cover at midday due to earlier day
convection. The airmass across this area has been slower to recover
as heating has been somewhat slower than surrounding areas.
Instability increases with southward extent, and to the east of a
surface trough, across southeast VA into northeast NC. With time,
much of the region should achieve moderate to strong destabilization
given surface dewpoints in the mid 70s F and temperatures climbing
into the upper 80s/low 90s F. Vertical shear will be strongest
(around 25-30 kt effective shear magnitudes) across northern
VA/MD/DE, while decreasing with southward extent into NC.

Convection may first develop in the uncapped and moderately unstable
airmass near the surface trough across parts of NC into southeast
VA. As airmass recovery continues across northern portions of the
MCD area, additional storms are expected to develop over the higher
terrain of northern VA and shift east through late afternoon/early
evening. Thunderstorm clusters will mainly pose a risk of damaging
gusts, with potentially some better organized/more intense bowing
segments possible further north where better shear overlaps the
moderately unstable airmass. Regardless, portions of the MCD area
will likely need severe thunderstorm watch issuance within the next
1-2 hours.

..Leitman/Gleason.. 06/30/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...PHI...AKQ...MHX...LWX...RAH...RNK...

LAT...LON   38267896 39487737 39637579 38897528 36947495 35997518
            35347621 35307850 35377947 35828018 36298023 37088010
            37567970 38267896