MESOSCALE DISCUSSION 1260
   NWS STORM PREDICTION CENTER NORMAN OK
   1228 PM CDT SAT JUN 23 2007
   
   AREAS AFFECTED...E CNTRL MO/SRN IL
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 231728Z - 231930Z
   
   THUNDERSTORMS ARE INCREASING FROM SOUTH CNTRL AND EAST CNTRL MO INTO
   SRN IL TO THE SOUTH OF A MID LEVEL VORTICITY MAX NEAR THE NERN
   MO/SERN IA BORDER.  ALTHOUGH ISOLATED SEVERE STORMS MAY BE POSSIBLE
   THIS AFTERNOON...WW IS NOT EXPECTED TO BE NEEDED.
   
   STORMS ARE FORMING IN WARM SECTOR OF WEAK SURFACE LOW LOCATED NEAR
   UIN...WHERE VISIBLE IMAGERY SHOWS BREAKS IN CLOUD COVER THAT ARE
   ALLOWING STRONGER DIABATIC HEATING AND DESTABILIZATION TO OCCUR. 
   SURFACE TEMPERATURES HAVE WARMED INTO THE LOW-MID 80S AND WITH DEW
   POINTS IN THE UPPER 60S...AIR MASS IS MODERATELY UNSTABLE WITH
   MLCAPE IN THE 1000-1500 J/KG RANGE.  HOWEVER...WEAK MID LEVEL LAPSE
   RATES WILL TEMPER VERTICAL ACCELERATION IN DEVELOPING UPDRAFTS AND
   MARGINAL VERTICAL SHEAR ASSOCIATED WITH 20 KT WINDS ALOFT SHOULD
   MODULATE DEGREE OF STORMSCALE ORGANIZATION...THUS LIMITING OVERALL
   SEVERE THREAT.  MARGINALLY SEVERE HAIL AND ISOLATED WET MICROBURSTS
   MAY OCCUR WITH STRONGER CELLS BUT OVERALL SEVERE POTENTIAL SHOULD
   REMAIN LIMITED.  WE WILL CONTINUE TO MONITOR THIS REGION BUT ATTM WW
   ISSUANCE IS NOT EXPECTED.
   
   ..WEISS.. 06/23/2007
   
   
   ATTN...WFO...PAH...ILX...LSX...SGF...
   
   37999322 38619220 39409104 39869038 39958965 39718873
   39028822 38418805 37848982 37479140 37289245 37589302