MESOSCALE DISCUSSION 0559
   NWS STORM PREDICTION CENTER NORMAN OK
   0802 PM CDT SUN APR 24 2011
   
   AREAS AFFECTED...CNTRL/ERN WV...NRN VA...WASHINGTON DC...CNTRL/SRN
   MD
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 250102Z - 250200Z
   
   ISOLATED THUNDERSTORMS HAVE DEVELOPED ACROSS A CORRIDOR EXTENDING
   FROM CNTRL WV EWD INTO NRN VA AND SRN MD. SOME OF THE STRONGER
   THUNDERSTORMS HAVE EXHIBITED WEAK MIDLEVEL ROTATION...AS EFFECTIVE
   BULK SHEAR VALUES ARE NEAR 40 KTS...THOUGH VERTICAL WIND PROFILES
   ARE LARGELY UNIDIRECTIONAL. ADDITIONALLY...MODERATELY STEEP MIDLEVEL
   LAPSE RATES /AROUND 6.5 C/KM PER 00Z IAD SOUNDING/ ARE SUPPORTING A
   THREAT FOR HAIL...WITH SOME POSSIBLY APPROACHING SVR LIMITS WITH THE
   STRONGEST CORES. WITH THE ONSET OF DIABATIC COOLING...ANY POTENTIAL
   FOR DMGG WINDS SHOULD BE RATHER LIMITED...AS THUNDERSTORMS WILL BE
   ROOTED ABOVE THE BOUNDARY LAYER. WEAK DEEP-LAYER FORCING WILL LIKELY
   KEEP THUNDERSTORM COVERAGE ISOLATED...WHICH SHOULD PRECLUDE THE NEED
   FOR A WW.
   
   ..ROGERS.. 04/25/2011
   
   
   ATTN...WFO...PHI...AKQ...LWX...RNK...PBZ...RLX...
   
   LAT...LON   38147629 38077829 38188000 38378073 38688091 39178052
               39387936 39377772 39407691 39337646 39177606 38727576
               38397576 38147629