MESOSCALE DISCUSSION 0304
   NWS STORM PREDICTION CENTER NORMAN OK
   0209 PM CDT SAT MAR 23 2013
   
   AREAS AFFECTED...TX...LA
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 231909Z - 232045Z
   
   PROBABILITY OF WATCH ISSUANCE...40 PERCENT
   
   SUMMARY...A PORTION OF ERN TX AND MUCH OF NRN LA CONTINUE TO BE
   MONITORED FOR AN INCREASING CHANCE FOR TSTM DEVELOPMENT INTO THE
   AFTERNOON HOURS. A WATCH REMAINS POSSIBLE ACROSS THESE AREAS.
   
   DISCUSSION...RECENT INCREASE IN TSTMS ACROSS WOOD...SMITH...AND
   HENDERSON COUNTIES IN E TX MAY BE THE FIRST SIGNS THAT STRONGER
   LARGE SCALE FORCING IS BEGINNING TO SPREAD EAST ACROSS THE REGION IN
   RESPONSE TO THE DIGGING VIGOROUS UPPER TROUGH ACROSS CO/NM. WHILE
   MUCH OF THE AREA FROM E TX INTO NRN LA WAS WELL NORTH OF
   SURFACE-BASED INSTABILITY AND A WARM/QUASI-STATIONARY FRONT ALONG
   THE UPPER TX COAST...INDICATIONS ARE THAT STEEP LAPSE RATES ABOVE
   THE STABLE SURFACE LAYER AND MOISTENING THROUGH THE LOWER LEVELS
   WILL CONTINUE TO CONTRIBUTE TO STRONG INSTABILITY. AS LIFT
   STRENGTHENS WITH THE APPROACH OF THE UPPER SYSTEM THROUGH THIS
   EVENING...EXPECT BOTH STORM COVERAGE AND INTENSITY TO INCREASE.
   DYNAMIC FORCING FOR ASCENT SHOULD BECOME INCREASINGLY FOCUSED ALONG
   AND NORTH OF WEAK FRONTAL WAVE CYCLONE TRACK. THIS LOW MAY BE TAKING
   SHAPE OVER E TX ATTM AND IS FORECAST TO DEVELOP ENEWD ACROSS CNTRL
   LA THROUGH THIS EVENING. CONTINUED DESTABILIZATION AND POTENT BULK
   SHEAR ON THE ORDER 50-60KT SHOULD PROMOTE STOUT AND PERSISTENT TSTM
   UPDRAFTS CAPABLE OF PRODUCING LARGE HAIL. WIND DMG AND SOME TORNADO
   POTENTIAL MAY INCREASE LATER AS LOW CENTER CONSOLIDATES OVER LA
   WHERE MODEST WARMING OF RECOVERING MARITIME TROPICAL AIRMASS COULD
   CONTRIBUTE TO SURFACE-BASED STORM INITIATION.
   
   ..CARBIN/HART.. 03/23/2013
   
   
   ATTN...WFO...JAN...LCH...SHV...
   
   LAT...LON   32789483 32159508 31539479 31029428 31039321 31119265
               31419160 32019127 32659125 32879179 33039439 32789483