SPC MD 1396

MD 1396 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PORTIONS OF NORTHERN WEST VIRGINIA…NORTHERN VIRGINIA…MARYLAND…DELAWARE…AND FAR SOUTHERN NEW JERSEY

MESOSCALE DISCUSSION 1396
NWS STORM PREDICTION CENTER NORMAN OK
0205 PM CDT MON JUL 25 2016

AREAS AFFECTED...PORTIONS OF NORTHERN WEST VIRGINIA...NORTHERN
VIRGINIA...MARYLAND...DELAWARE...AND FAR SOUTHERN NEW JERSEY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 251905Z - 252100Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...THE POTENTIAL FOR ISOLATED DAMAGING WIND GUSTS IS
INCREASING OVER THE NEXT FEW HOURS TO THE SOUTH OF WATCH 0415.
TRENDS WILL CONTINUE TO BE MONITORED FOR A POTENTIAL SEVERE
THUNDERSTORM WATCH.

DISCUSSION...STRONG HEATING WITHIN A VERY MOIST BOUNDARY LAYER HAS
CONTRIBUTED TO A CONDITIONALLY UNSTABLE AIR MASS...WITH MIXED-LAYER
CAPE VALUES RANGING FROM 2000-3000 J/KG ACROSS THE AREA. DESPITE
SURFACE DEWPOINTS IN THE UPPER 60S TO LOW 70S /AND EVEN HIGHER
DEWPOINTS OVER THE DELMARVA PENINSULA/ BOUNDARY LAYER TOPS ARE
RATHER HIGH OWING TO RAPID AND DEEP MIXING FACILITATED BY THE MODEST
WESTERLY FLOW OVER THE LOWEST 2-3 KM. THE AREA IS ON THE SOUTHERN
FRINGE OF THE STRONGER 700-300 MB FLOW THAT IS CONTRIBUTING TO
EFFECTIVE BULK SHEAR OF 25-35 KT. GIVEN THE MODEST
FLOW/SHEAR...THUNDERSTORMS THAT ARE CURRENTLY DEVELOPING OVER THE
WESTERN PART OF THE AREA SHOULD REMAIN MOSTLY DISORGANIZED AS THEY
MOVE EAST THROUGH THE AFTERNOON. HOWEVER...ISOLATED DAMAGING WIND
GUSTS/MICROBURSTS ARE POSSIBLE WITH THE STRONGER CELLS AND
DOWNDRAFTS OWING TO STRONG SUB-CLOUD EVAPORATION POTENTIAL. TRENDS
IN CONVECTIVE ORGANIZATION/COVERAGE WILL BE MONITORED CLOSELY.

..CONIGLIO/WEISS.. 07/25/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PHI...AKQ...LWX...RNK...PBZ...RLX...

LAT...LON   39567832 39537721 39507671 39477600 39377546 39107514
            38847501 38497521 37917574 37617630 37597712 37757825
            37987938 38118020 38158089 38538131 38898132 39168115
            39448080 39748045 39657965 39567832 

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