MESOSCALE DISCUSSION 0761
   NWS STORM PREDICTION CENTER NORMAN OK
   0236 PM CDT THU MAY 12 2011
   
   AREAS AFFECTED...ERN OH THROUGH EXTREME WRN PA AND NRN AND CNTRL WV
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 290...
   
   VALID 121936Z - 122100Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 290
   CONTINUES.
   
   THREAT FOR MAINLY ISOLATED LARGE HAIL AND LOCALLY STRONG WIND GUSTS
   WILL PERSIST NEXT COUPLE HOURS FROM ERN OH ...WRN PA SWD INTO CNTRL
   WV.
   
   STORMS CONTINUE REDEVELOPING...PRIMARILY IN VICINITY OF CONVECTIVE
   OUTFLOW BOUNDARY THAT EXTENDS FROM NRN OH SWD THROUGH CNTRL WV.
   EFFECTIVE VERTICAL SHEAR IS WEAK /20-30 KT/ DUE TO PROXIMITY OF
   UPPER RIDGE...AND THIS HAS BEEN A LIMITING FACTOR FOR A MORE ROBUST
   SEVERE EVENT. HOWEVER...MODERATE INSTABILITY AND 6.5-7 C/KM MID
   LEVEL LAPSE RATES SUPPORT AT LEAST A MODEST THREAT FOR ISOLATED
   LARGE HAIL AS WELL AS LOCALLY STRONG WIND GUSTS.
   
   ..DIAL.. 05/12/2011
   
   
   ATTN...WFO...PBZ...RLX...CLE...ILN...
   
   LAT...LON   41498138 40088081 38928045 38308064 38438111 39548189
               40828261 41268258 41498138