MESOSCALE DISCUSSION 0856
   NWS STORM PREDICTION CENTER NORMAN OK
   1235 PM CDT TUE MAY 22 2007
   
   AREAS AFFECTED...SCENTRAL TX/MIDDLE TX COASTAL PLAINS
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 221735Z - 221930Z
   
   AN ISOLATED SVR TSTM OR TWO MAY DEVELOP ALONG THE MIDDLE TX COASTAL
   PLAINS OF SCENTRAL TX IN THE NEXT 2-3 HOURS. A WW IS NOT EXPECTED
   GIVEN THE LACK OF GREATER AREAL COVERAGE/MARGINAL NATURE OF THE SVR
   THREAT. 
   
   LATEST VISIBLE SATELLITE IMAGERY SHOWS MODERATE CU DEVELOPING ALONG
   BOTH A N-S ORIENTED CONFLUENT AXIS AND AN OUTFLOW BOUNDARY IN MIDDLE
   TX COASTAL PLAINS INVOF MATAGORDA BAY. A MODIFIED 12Z CRP SOUNDING
   INDICATES LESS THAN 25 J/KG OF MLCINH ACROSS THE AREA WITH AROUND
   2000 J/KG OF MLCAPE. RECENT SFC ANALYSIS SHOWS MODERATE CONVERGENCE
   ALONG THE OUTFLOW BOUNDARY. GIVEN CONTINUED HEATING AND
   DESTABILIZATION...AN  ISOLATED SVR TSTM MAY DEVELOP...ESPECIALLY
   INVOF OF THE OUTFLOW BOUNDARY/CONFLUENCE TROUGH INTERSECTION INVOF
   MATAGORDA BAY WHERE CONVERGENCE IS MAXIMIZED.  15-20 KTS BACKED
   ESELY LOW LEVEL FLOW ALONG AND JUST EAST OF THE OUTFLOW BOUNDARY
   WILL AUGMENT WEAKER MID LEVEL FLOW TO SUPPORT SUFFICIENTLY STRONG
   VERTICAL SHEAR PROFILES OF 35-40 KTS TO SUPPORT SUPERCELL STORM
   STRUCTURE. THUS DESPITE VERY WARM TEMPERATURES...MARGINAL SVR
   HAIL/DMGG WINDS GUSTS WILL BE POSSIBLE.
   
   ..CROSBIE.. 05/22/2007
   
   
   ATTN...WFO...HGX...CRP...EWX...
   
   27839696 27849742 28269773 28699783 29479758 29669744
   29529675 28609600 28279617