MESOSCALE DISCUSSION 1276
   NWS STORM PREDICTION CENTER NORMAN OK
   0625 PM CDT MON JUN 22 2009
   
   AREAS AFFECTED...PARTS OF THE LOWER OH RIVER VALLEY
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 222325Z - 230030Z
   
   POTENTIAL APPEARS TO BE INCREASING FOR AN ORGANIZED STRONG/SEVERE
   CLUSTER ACROSS PARTS OF THE LOWER OH RIVER VALLEY AND PERHAPS AS FAR
   S AS MIDDLE TN.  
   
   RADAR MOSAIC TRENDS OVER THE PAST HOUR HAVE SHOWN AN INCREASE IN
   TSTM COVERAGE FROM SERN IL TO 20 MI N BWG.  RADAR/SURFACE ANALYSIS
   INDICATE A NWWD ARCING OUTFLOW BOUNDARY FROM NEAR NASHVILLE NNWWD
   TOWARDS EVANSVILLE.  THE AIRMASS IMMEDIATELY TO THE W OF THIS
   BOUNDARY/RESIDUAL STATIONARY FRONT HAS BECOME MODERATELY-VERY
   UNSTABLE AS STRONG AFTERNOON HEATING HAS LED TO TEMPS RISING INTO
   THE LOWER TO MID 90S.  
   
   AS LEADING EDGE OF STORM CLUSTER OVER W-CNTRL KY CONTINUES TO
   ORGANIZE ITS COLD POOL...EXPECT STORMS TO BEGIN TO ACCELERATE TO THE
   SSE TOWARDS THE BWG VICINITY AND POINTS S THE NEXT FEW HOURS.  AN
   INITIAL THREAT FOR MARGINALLY SEVERE HAIL WILL LIKELY WANE AS
   FORWARD PROPAGATING TSTM/COLD POOL DEVELOPMENT POSES MAINLY AN ISOLD
   DMGG WIND THREAT.  FOCUSED LOW LEVEL CONVERGENCE OVER SERN IL MAY
   CONTINUE TO AID IN BACKBUILDING/ADDITIONAL STATIONARY UPWIND
   DEVELOPMENT AS INDIVIDUAL STORMS MOVE SEWD TOWARDS THE WABASH/OH
   RIVER CONFLUENCE.  WITH PRECIPITABLE WATER VALUES NEAR 2
   INCHES...VERY HEAVY RAINFALL RATES /UP TO 3 INCHES PER HOUR/ MAY
   RESULT.
   
   ..SMITH.. 06/22/2009
   
   
   ATTN...WFO...LMK...OHX...IND...PAH...ILX...LSX...
   
   LAT...LON   36158720 37668811 38798878 39068847 39038812 38538763
               38078725 37758643 36988599 36208627 35938655 36158720