MESOSCALE DISCUSSION 0269
   NWS STORM PREDICTION CENTER NORMAN OK
   0457 PM CDT SUN MAR 11 2007
   
   AREAS AFFECTED...CENTRAL TX
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 112157Z - 112330Z
   
   SEVERE THREAT IS INCREASING ACROSS CENTRAL TX AND A NEW WW WILL
   LIKELY BE REQUIRED FOR AREAS E OF WW 57.
   
   MOISTURE RETURN CONTINUES ACROSS S TX WITH MID 60S DEWPOINTS INTO
   THE SAN ANTONIO AREA. AREA VWPS INDICATE 925-850 FLOW 20-30 KTS
   BENEATH MODEST 30-40 KT MID LEVEL FLOW. THIS WILL CONTINUE TO ADVECT
   RICH MOISTURE NWWD AND IS PRODUCING HODOGRAPHS FAVORABLE FOR
   SUPERCELLS...WITH EFFECTIVE SRH VALUES OF 150-200 M2/S2 NOTED ON GRK
   AND EWX RADARS.
   
   STORMS CURRENTLY OVER CNTRL TX HAVE STRUGGLED MAINLY DUE TO
   RELATIVELY COOL BOUNDARY LAYER TEMPERATURES. HOWEVER...COOLING ALOFT
   AND UPDRAFT PERSISTENCE MAY ALLOW THESE STORMS TO EVENTUALLY POSE A
   THREAT. REGARDLESS...THE ENVIRONMENT REMAINS FAVORABLE FOR
   SUSTAINING SEVERE STORMS. SEVERE BOW CURRENTLY MOVING EWD ACROSS NRN
   WW 57 WILL EMERGE INTO TAYLOR AND RUNNELS COUNTIES BY AROUND 23Z AS
   IT TRACKS EWD AROUND 30 MPH. SEVERE WIND AND HAIL WILL BE THE MAIN
   THREATS...BUT A TORNADO THREAT WILL ALSO EXIST WITH THE MORE
   ISOLATED STORMS GIVEN SURFACE BASED EFFECTIVE INFLOW LAYERS.
   
   ..JEWELL.. 03/11/2007
   
   
   ATTN...WFO...FWD...EWX...SJT...
   
   29090007 30720003 32140049 32719940 32699813 32289766
   31119735 29979746 29179792 29059866 29049935