MESOSCALE DISCUSSION 0902
   NWS STORM PREDICTION CENTER NORMAN OK
   0601 PM CDT SAT MAY 30 2009
   
   AREAS AFFECTED...ERN/SRN IL...WRN/SRN IND...SW OH...NRN/ERN KY AND
   CENTRAL/SRN WV
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 316...
   
   VALID 302301Z - 310000Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 316
   CONTINUES.
   
   A NEW WW MAY BE NEEDED TO THE NORTH OF WW 316 FROM PARTS OF NERN IL
   INTO CENTRAL IND.  HOWEVER...WEAKER INSTABILITY WITH NWD EXTENT
   SUGGESTS OVERALL COVERAGE FOR A SEVERE WEATHER THREAT MAY BE LOW AND
   PRECLUDE A WATCH ISSUANCE.  IF STORMS SHOW SIGNS OF INCREASING IN
   COVERAGE/INTENSITY...THEN A NEW WW WOULD BE NEEDED.
   
   EARLY EVENING SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE OVER
   NERN IL WITH A COLD FRONT TRAILING SWWD INTO WEST CENTRAL IL...WHILE
   ANOTHER FRONT EXTENDED SEWD THROUGH CENTRAL/SERN IND TO FAR SWRN OH
   AND CENTRAL KY.  
   
   ...IL/IND/SW OH/NORTH CENTRAL KY...
   REGIONAL RADARS/LIGHTNING DATA INDICATED AN INCREASE IN TSTM
   COVERAGE WITHIN THE WARM SECTOR OVER CENTRAL IL AND ALONG THE
   SURFACE FRONT EXTENDING SEWD THROUGH NWRN/CENTRAL IND.  ASCENT
   ATTENDANT TO A WEAK MID LEVEL IMPULSE TRANSLATING THROUGH THE NW
   FLOW REGIME ACROSS THE MIDWEST IS EXPECTED TO SUPPORT ADDITIONAL
   TSTM DEVELOPMENT ESEWD THROUGH ERN IL/CENTRAL IND TO SW OH THIS
   EVENING.  ALTHOUGH STRONGEST INSTABILITY /MLCAPE 1000-2000 J/KG/ AND
   DEEP LAYER SHEAR RESIDES WITHIN THE WARM SECTOR...SUFFICIENT SHEAR
   /35-45 KT/ NORTH OF THE IND/OH FRONT SUGGESTS A POTENTIAL FOR
   ORGANIZED STORMS DESPITE WEAKER INSTABILITY WITH NWD EXTENT.  WIND
   PROFILER AT WLC SHOWED A STRAIGHT HODOGRAPH SUGGESTING A CONTINUED
   LIKELIHOOD FOR SPLITTING STORMS...WITH STRONG WIND GUSTS/HAIL
   POSSIBLE WITH STRONGER ACTIVITY.
   
   ..SOUTH CENTRAL OH/ERN KY/WV...
   ASCENT ATTENDANT TO A WEAK LEAD MID LEVEL IMPULSE/MCV SHOULD SUPPORT
   ADDITIONAL TSTMS THAT DEVELOP IN VICINITY OF THE SURFACE FRONT. 
   MODERATE INSTABILITY AND EFFECTIVE SHEAR 40-50 KT WILL CONTINUE TO
   MAINTAIN LIKELIHOOD FOR ORGANIZED SEVERE STORMS PRODUCING HAIL AND
   STRONG WIND GUSTS.  GIVEN CONTINUED DEVELOPMENT OF STORMS ACROSS THE
   ERN PART OF WW 316...LOCAL WFO EXTENSION OF THIS WATCH IS POSSIBLE
   INTO THE REST OF SRN WV.
   
   ..PETERS.. 05/30/2009
   
   
   ATTN...WFO...RNK...RLX...MRX...JKL...ILN...LMK...IWX...IND...
   PAH...LOT...ILX...LSX...
   
   LAT...LON   38348947 38769041 40129061 40668934 41308820 41248719
               40568560 40118470 39678422 39048235 38648107 38048059
               37298124 37058214 38348947