MESOSCALE DISCUSSION 1554
   NWS STORM PREDICTION CENTER NORMAN OK
   0326 PM CDT WED AUG 17 2016

   AREAS AFFECTED...CNTRL AND NRN VA / CNTRL AND SRN MD / DE

   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

   VALID 172026Z - 172130Z

   PROBABILITY OF WATCH ISSUANCE...60 PERCENT

   SUMMARY...THE THREAT FOR ISOLATED DAMAGING WINDS OWING PRIMARILY TO
   40-60 MPH GUSTS WILL PROBABLY MOVE TO THE I-95 CORRIDOR BY EARLY
   EVENING.  A SEVERE THUNDERSTORM WATCH MAY NEED TO BE CONSIDERED BY
   21 UTC.

   DISCUSSION...RADAR IMAGERY SHOWS SEVERAL LOOSELY ORGANIZED LINEAR
   CLUSTERS MOVING EWD ACROSS WV AND PORTIONS OF WRN VA.  THE STRONGEST
   INSTRUMENT-MEASURED GUSTS /I.E. 41-KT/ HAVE OCCURRED AT KBKW AND
   KFVX BETWEEN 1920-2000 UTC.  A MID-LEVEL PERTURBATION ASSOCIATED
   WITH THE WV STORM CLUSTER WILL CONTINUE ENEWD AS ACROSS THE CNTRL
   APPALACHIANS THIS AFTERNOON AHEAD OF A WEAK SHORTWAVE TROUGH OVER
   THE GREAT LAKES.  SURFACE CONDITIONS E OF THE HIGHER TRAIN IN
   CNTRL/NRN VA HAVE WARMED INTO THE LOWER 90S WITH LOW 70S DEWPOINTS. 
   THIS REGION RESIDES ON THE SRN FRINGE OF STRONGER WLY/S WITH
   EFFECTIVE SHEAR MAGNITUDES AROUND 20-25 KT.  AS A RESULT...COLD POOL
   ORGANIZATION POTENTIAL WILL REMAIN SUFFICIENT FOR MAINTAINING
   SEMI-ORGANIZED MULTICELLS CAPABLE OF ISOLATED WIND GUSTS IN THE
   40-60 MPH RANGE -- EFFECTIVELY CAPABLE OF LOCALIZED DAMAGING GUSTS
   WITH THE STRONGER WATER-LOADED DOWNDRAFTS.  THIS ACTIVITY WILL
   LIKELY MOVE EWD INTO THE CHESAPEAKE BAY/DELMARVA VICINITY THIS
   EVENING BUT SOME UNCERTAINTY REMAINS REGARDING THE POTENTIAL FOR
   DAMAGING GUSTS AFTER SUNSET AS IT MOVES INTO THIS AREA.

   ..SMITH/DARROW.. 08/17/2016


   ATTN...WFO...PHI...AKQ...LWX...RNK...

   LAT...LON   37357963 39657742 39347547 38597504 37777548 37247584
               37357963