MESOSCALE DISCUSSION 0470
   NWS STORM PREDICTION CENTER NORMAN OK
   1240 PM CDT TUE APR 19 2011
   
   AREAS AFFECTED...SW-CNTRL-ERN MO...SW IL...FAR NW AR...NE OK AND FAR
   SE KS
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 191740Z - 191915Z
   
   A SEVERE THREAT IS EXPECTED TO DEVELOP FROM CNTRL AND ERN MO SWWD
   ACROSS SW MO AND FAR SE KS THIS AFTERNOON. LARGE HAIL AND WIND
   DAMAGE WILL BE POSSIBLE WITH THE MORE INTENSE CELLS. A TORNADO
   THREAT MAY DEVELOP LATE THIS AFTERNOON ACROSS CNTRL-ERN MO AND SW
   IL. A TORNADO WATCH WILL LIKELY BE NECESSARY ACROSS THE REGION OVER
   THE NEXT HOUR.
   
   LATEST SFC ANALYSIS SHOWS A 998 MB SFC LOW IN WRN MO WITH A
   QUASI-STATIONARY FRONT EXTENDING EWD ACROSS SRN IL AND SRN IND. A
   COLD FRONT EXTENDS SWWD FROM THE LOW ACROSS FAR SE KS INTO NE OK.
   CURRENT MESOANALYSIS IS SHOWING A WEAKENING CAPPING INVERSION NEAR
   THE SFC LOW IN WRN MO WITH LOW-LEVEL CONVERGENCE BECOMING FOCUSED
   ALONG THE COLD FRONT. THIS SHOULD RESULT IN STORM INITIATION IN WRN
   MO OVER THE NEXT HOUR WHERE ECHOES ARE STARTING TO BE OBSERVED NEAR
   THE KS-MO STATE-LINE. MLCAPE VALUES OF 2500 TO 3500 J/KG AND
   MODERATE DEEP LAYER SHEAR SHOULD SUPPORT SUPERCELL DEVELOPMENT WITH
   A LARGE HAIL AND WIND DAMAGE THREAT.
   
   ADDITIONAL STORM INITIATION IS EXPECTED TO OCCUR ALONG THE
   STATIONARY FRONT CNTRL MO EWD INTO SW IL. IN ADDITION TO THE STRONG
   INSTABILITY AND DEEP LAYER SHEAR...LOW-LEVEL SHEAR PROFILES SHOULD
   BE FAVORABLE FOR A TORNADO THREAT WITH THIS THREAT INCREASING LATER
   THIS AFTERNOON AND STORMS MATURE.
   
   ..BROYLES.. 04/19/2011
   
   
   ATTN...WFO...LSX...SGF...EAX...TSA...ICT...
   
   LAT...LON   37679278 38069213 38089030 38468967 38968968 39139018
               39169293 38089427 36979512 36009534 35899446 37679278