ZCZC SPCSWOMCD ALL
ACUS11 KWNS 141924 
SPC MCD 141924 
MDZ000-VAZ000-DCZ000-WVZ000-142130-

Mesoscale Discussion 1284
NWS Storm Prediction Center Norman OK
0224 PM CDT Wed Jul 14 2021

Areas affected...northern Virginia into Maryland

Concerning...Severe potential...Watch unlikely 

Valid 141924Z - 142130Z

Probability of Watch Issuance...20 percent

SUMMARY...A cluster of storms may produce strong wind gusts capable
of localized damage over the next few hours.

DISCUSSION...Steep low-level lapse rates have developed near a weak
surface trough, resulting in deep mixed layers per modified forecast
soundings. A small cluster of storms has already formed over
northern VA, consistent with earlier CAM depictions, and these cells
are likely to propagate east/southeast over the next few hours.
Deep-layer shear is weak, but perhaps sufficient to sustain and
advect these storms eastward given the deep mixed layers and
sufficient instability. As such, localized damaging gusts cannot be
ruled out. Storms are expected to remain tied to the diurnal cycle,
and weaken by evening.

..Jewell/Bunting.. 07/14/2021

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

ATTN...WFO...AKQ...LWX...

LAT...LON   37937729 37877831 38107861 38397842 39037828 39317779
            39367706 39187662 38757648 38357649 38227660 37937729 

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