MESOSCALE DISCUSSION 0562
   NWS STORM PREDICTION CENTER NORMAN OK
   0127 PM CDT SAT APR 25 2009
   
   AREAS AFFECTED...SOUTHEAST TX PANHANDLE...WESTERN OK...SOUTH CENTRAL
   KS
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 251827Z - 252100Z
   
   CORRECTED FOR INTERSTATE NUMBER
   
   A TORNADO WATCH WILL BE REQUIRED BEFORE 22Z. 
   
   IN WAKE OF A LEAD DISTURBANCE MOVING ACROSS THE CENTRAL
   PLAINS...SATELLITE SUGGESTS WEAK RIDGING RAPIDLY TRANSLATING OUT OF
   NM.  BACK EDGE OF THE LARGE SCALE RIDGING IS EXTRAPOLATED TO CLEAR
   THE SOUTHERN HIGH PLAINS 21-22Z WITH INCREASING LARGE SCALE ASCENT
   THEREAFTER.
   
   COLD FRONT HAS ESSENTIALLY STALLED FROM NORTHWEST OF
   WICHITA-WOODWARD-AMARILLO WITH THE DRYLINE BEGINNING TO MIX EAST
   ALONG THE I-27 CORRIDOR.  CLEARING NORTH OF THE FRONT MAY SIGNAL
   THAT THE BOUNDARY WILL MOVE SLIGHTLY NORTHWEST THROUGH LATE
   AFTERNOON AS THE DRYLINE MIXES INTO THE SOUTHEAST TX PANHANDLE.
   
   THUNDERSTORM INITIATION SHOULD TAKE PLACE AROUND 22Z ALONG THE
   DRYLINE/FRONT OVER THE SOUTHEAST TX PANHANDLE INTO SOUTH-CENTRAL
   KS...THEN BUILD SOUTHWARD ALONG THE DRYLINE TOWARD CHILDRESS 22-00Z.
    MLCAPES WILL RANGE 2000-2500 J/KG.  
   
   SOMEWHAT ANEMIC VERTICAL SHEAR PROFILES NOTED CURRENTLY SHOULD
   IMPROVE BY INITIATION TIME AS STRONGER SOUTHWESTERLY MID-LEVEL WINDS
   OVER THE SOUTHERN ROCKIES EDGE SOUTHEASTWARD.  WIND PROFILES WILL
   BECOME VERY CONDUCIVE FOR SUPERCELLS WITH GIANT HAIL GREATER THAN 2
   INCHES IN DIAMETER.  IN FACT...AS THE GREAT BASIN UPPER TROUGH
   CONTINUES TOWARD THE SOUTHERN ROCKIES...SOUTHERLY BOUNDARY LAYER
   FLOW IS EXPECTED TO INCREASE TO OVER 55 KTS DURING THE EVENING. 
   THIS WILL NOT ONLY MAINTAIN DISCRETE SUPERCELL STRUCTURES AS RICH
   MOISTURE INFLOW CONTINUES...BUT ALSO BOOST 0-1KM STORM RELATIVE
   HELICITY TO AT OR ABOVE 400 M2/S2.  THIS WILL LIKELY YIELD
   LONG-LIVED SUPERCELLS WITH POSSIBLE STRONG TORNADOES WHICH MAY LAST
   WELL BEYOND SUNSET ACROSS WEST-CENTRAL/ NORTH-CENTRAL OK INTO
   SOUTH-CENTRAL KS.
   
   ..RACY.. 04/25/2009
   
   
   ATTN...WFO...ICT...OUN...DDC...LUB...AMA...
   
   LAT...LON   34260079 35560082 37729774 37779705 36049761 34379845
               34259973 34260079