MESOSCALE DISCUSSION 0480
   NWS STORM PREDICTION CENTER NORMAN OK
   0847 PM CDT TUE APR 19 2011
   
   AREAS AFFECTED...CNTRL/SWRN OH...NWRN/CNTRL KY
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 200147Z - 200315Z
   
   A WW WILL LIKELY BE REQUIRED DOWNSTREAM OF ONGOING CONVECTION...
   INCLUDING CNTRL/SWRN OH AND NWRN/CNTRL KY.
   
   A FORWARD-PROPAGATING QLCS CONTINUES TRACKING EWD AT 40 TO 50 KT
   OVER CNTRL IND...CNTRL/SRN IL...AND SERN MO...WITH DISTINCT BOWING
   SEGMENTS OVER SRN IL AND CNTRL IND. THE QLCS WILL CONTINUE TRACKING
   EWD AS IT TRAVERSES THE BROAD MOIST/UNSTABLE SECTOR SOUTH OF A WARM
   FRONT DRAPED ACROSS CNTRL IND/OH...WITH MLCAPE VALUES AOA 1000 J/KG
   SOUTH OF THE FRONT. THE PRIMARY THREAT WILL BE DMGG WINDS...
   ESPECIALLY WITH WELL-DEFINED BOWING SEGMENTS...THOUGH STRONG
   LOW-LEVEL WIND SHEAR /444 M2 PER S2 OF EFFECTIVE SRH PER 00Z ILN
   SOUNDING/ WILL SUSTAIN THE THREAT FOR A FEW TORNADOES WITH EMBEDDED
   MESOVORTICES. STRONG FORWARD PROPAGATION WILL CONTINUE GIVEN THE
   ORTHOGONAL COMPONENT OF THE DEEP-LAYER WIND SHEAR RELATIVE TO THE
   LEADING CONVECTIVE LINE...WITH THE STORMS LIKELY MOVING INTO WRN OH
   AND NWRN KY AFTER 0330Z. THUS...A NEW WW WILL LIKELY BE REQUIRED
   DOWNSTREAM OF THE ONGOING CONVECTION.
   
   ..COHEN.. 04/20/2011
   
   
   ATTN...WFO...ILN...LMK...
   
   LAT...LON   37458673 39138519 40258416 40108271 38528402 36958542
               36768666 37458673