MESOSCALE DISCUSSION 1516
   NWS STORM PREDICTION CENTER NORMAN OK
   0421 AM CDT WED JUL 18 2007
   
   AREAS AFFECTED...SE IL...SW IND
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 180921Z - 181015Z
   
   A WIND DAMAGE THREAT MAY DEVELOP ACROSS SE IL AND SW IND OVER THE
   NEXT 1 TO 3 HOURS. IF THE BOWING MCS PERSISTS AND ORGANIZES
   FURTHER...A WW MAY BECOME NECESSARY ACROSS THE REGION LATER THIS
   MORNING.
   
   LATEST SFC ANALYSIS SHOWS A LOW OVER NW IA WITH A WARM FRONT
   EXTENDING SEWD TO NEAR LINCOLN IL. NORTHEAST OF THE
   BOUNDARY...OBJECTIVE ANALYSIS INDICATES STRONG ELEVATED INSTABILITY
   EXISTS WITH MUCAPE VALUES EXCEEDING 2500 J/KG ACROSS MOST OF ECNTRL
   IL AND SW IND. THIS SUGGEST THE BOWING LINEAR MCS MAY CONTINUE TO
   PERSIST FOR SEVERAL MORE HOURS MOVING SWD ALONG THE AXIS OF STRONG
   INSTABILITY APPROACHING THE OH RIVER BY 11Z TO 12Z. EVEN THOUGH
   RECENT RADAR TRENDS SUGGEST THE BOWING MCS IS STILL
   UNORGANIZED...THE RAINTOUL IL OBSERVATION REPORTED A 37 KT WIND GUST
   AT 0905Z. THE STRONG INSTABILITY AND RELATIVELY FAST FORWARD SPEED
   OF THE BOW AROUND 45 KT SUGGESTS A WIND DAMAGE POTENTIAL MAY DEVELOP
   WITH THE MCS THROUGH DAYBREAK. HIGH PRECIPITABLE WATER VALUES ALONG
   THE INSTABILITY AXIS WILL ALSO MAKE VERY HEAVY RAIN LIKELY WITH THE
   MORE INTENSE CELLS.
   
   ..BROYLES.. 07/18/2007
   
   
   ATTN...WFO...LMK...IND...PAH...ILX...
   
   40028883 40038805 40208736 39628692 38868668 38358677
   38028735 38008777 38218822 38918868 39508886