MESOSCALE DISCUSSION 1006
   NWS STORM PREDICTION CENTER NORMAN OK
   0342 PM CDT SAT MAY 28 2011
   
   AREAS AFFECTED...CNTRL IL...WRN INDIANA
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 393...
   
   VALID 282042Z - 282215Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 393
   CONTINUES.
   
   A SEVERE HAIL THREAT WILL PERSIST ACROSS THE AREA FOR THE REST OF
   THE AFTERNOON...ESPECIALLY ACROSS THE SRN PART OF WW 393. 
   
   LATEST RADAR SHOWS AN INTENSE ELEVATED SUPERCELL CURRENTLY OVER
   SHELBY CO ILLINOIS...WITH A LARGER CLUSTER OF CONVECTION LOCATED TO
   THE NORTH. THIS ACTIVITY IS LOCATED ON THE LEADING EDGE OF A STEEP
   LAPSE RATE PLUME EXTENDING FROM OK INTO SRN MO AND IS BEING AIDED BY
   A 35-40 KT SWLY LOW-LEVEL JET. MU CAPE OF 1000-2000 J/KG AND
   EFFECTIVE SHEAR OF 40-50 KTS WILL CONTINUE TO PROMOTE STORM
   ORGANIZATION. 
   
   CURRENT ACTIVITY WILL LIKELY OUTPACE THE ADVANCE OF THE MID-LEVEL
   LAPSE RATE PLUME AND MAY BEGIN TO WEAKEN AS IT APPROACHES THE ERN
   EDGE OF THE WATCH. THE SHELBY CO SUPERCELL MAY CONTINUE TO BE A
   PROLIFIC HAIL PRODUCER FOR THE NEXT 1-2 HRS BEFORE THE ENVIRONMENT
   BECOMES LESS FAVORABLE.
   
   ..DEAN.. 05/28/2011
   
   
   ATTN...WFO...IWX...IND...LOT...ILX...LSX...
   
   LAT...LON   39148900 39508961 39978976 40168963 40418905 40618861
               40828801 40928722 40938660 40888610 40628583 40168579
               39748582 39368608 39098655 38878702 38808766 38878835
               38968853 39148900