MESOSCALE DISCUSSION 0568
   NWS STORM PREDICTION CENTER NORMAN OK
   0615 PM CDT SAT APR 25 2009
   
   AREAS AFFECTED...SRN MI...NERN IND...EXTREME NWRN OH
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 182...
   
   VALID 252315Z - 260015Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 182
   CONTINUES.
   
   THUNDERSTORM LINE SEGMENTS DISPLAYING OCCASIONAL BOWING STORM
   STRUCTURE ARE MOVING E AT 40 KT OVER SERN MI...WITH OTHER MORE
   DISCRETE ACTIVITY TRAILING TO THE WSW OVER SCNTRL MI. THESE STORMS
   HAVE OCCASIONALLY PRODUCED WIND GUSTS NEAR SVR LVLS...WITH A 40 KT
   GUST RECENTLY REPORTED NEAR ANN ARBOR. ADDITIONAL THUNDERSTORM
   DEVELOPMENT IS OCCURRING OVER NERN IL...AND WILL MOVE E INTO WW 182
   DURING THE NEXT SEVERAL HRS. 
   
   PRIMARY SURFACE FRONT AT 22Z WAS LOCATED OVER NRN IL EXTENDING
   E-NEWD INTO SERN-CNTRL MI. A THERMAL GRADIENT EXISTED S OF THE FRONT
   OVER SRN MI...WHERE TEMPERATURES STILL RESIDE IN THE 70S AND 80S AND
   DEWPOINTS WHERE IN THE 50S TO LWR 60S. MODIFIED RUC SOUNDINGS FOR
   SRN MI AIRMASS YIELD AROUND 1000 J/KG OF MLCAPE. IN ADDITION...AREA
   VWP AND SHORT TERM MODEL GUIDANCE CONTINUE TO INDICATE FAST
   UNI-DIRECTIONAL DEEP LAYER FLOW AROUND 40-50 KT OVER THE
   REGION...FAVORING FAST MOVING LINE SEGMENTS THAT WILL CONTINUE TO
   POSE A THREAT OF DAMAGING WINDS. THOUGH STORMS WITH A HISTORY OF
   DAMAGING WIND ARE BEGINNING TO EXIT WW...STORMS CROSSING LAKE
   MICHIGAN MAY INTENSIFY DURING THE NEXT FEW HRS OVER SRN MI.
   THUS...THE SVR THREAT CONTINUES ACROSS MUCH OF WW 182.
   
   ..GARNER.. 04/25/2009
   
   
   ATTN...WFO...CLE...DTX...IWX...GRR...
   
   LAT...LON   42608702 43598229 42028187 41038662 42608702