MESOSCALE DISCUSSION 1105
   NWS STORM PREDICTION CENTER NORMAN OK
   0535 PM CDT SUN JUN 05 2011
   
   AREAS AFFECTED...ERN TX...WRN LA...FAR SWRN AR
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 052235Z - 060030Z
   
   LATEST GPS TOTAL PRECIPITABLE WATER IMAGERY DEPICTS A WWD-MOVING
   SURGE IN MODESTLY INCREASED DEEP-LAYER MOISTURE...WITH PWAT VALUES
   GENERALLY FROM 1.2 TO 1.6 INCHES ALONG AND EAST OF INTERSTATE 35.
   STRONG DIABATIC HEATING HAS ALLOWED TEMPERATURES TO WARM INTO THE
   UPPER 90S TO NEAR 100 DEGREES AMIDST THIS RELATIVELY MORE MOIST AIR
   MASS...YIELDING MLCAPE VALUES FROM 1000 TO 2500 J/KG WITHOUT ANY
   APPRECIABLE CONVECTIVE INHIBITION. THIS HAS GIVEN RISE TO ISOLATED
   TO WIDELY SCATTERED CONVECTION...WHICH WILL CONTINUE THROUGH THE
   REMAINDER OF THE AFTERNOON HOURS.
   
   THREE REGIMES OF CONVECTIVE ACTIVITY WILL PERSIST INTO THE EARLY
   EVENING:
   1. ACROSS PORTIONS OF SERN TX...CONVERGENCE LEADING WWD/WSWWD-MOVING
   COLD POOLS WILL CONTINUE TO RESULT IN PULSE-LIKE CONVECTION.
   OCCASIONAL...BRIEF...AND LOCALIZED AREAS OF UPSCALE GROWTH COULD
   OCCUR WITH MERGING COLD POOLS...ESPECIALLY INVOF THE SEA BREEZE
   LIFTING NWD NEAR THE HIGHWAY 59 CORRIDOR IN SERN TX AND AN AGGREGATE
   OUTFLOW BOUNDARY DROPPING SOUTH TOWARD THE INTERSTATE 10 CORRIDOR.
   
   2. ACROSS PORTIONS OF NERN TX...FAR SWRN AR...AND NWRN
   LA...SHREVEPORT 0.5-DEGREE RADAR REFLECTIVITY DEPICTS A WELL-DEFINED
   OUTFLOW BOUNDARY SURGING SWD ALONG THE SABINE RIVER...WITH LOCALIZED
   STORM-SCALE ASCENT ATOP THE ASSOCIATED COLD POOL. WHILE THIS COULD
   PROVIDE A TEMPORARY ENHANCEMENT TO ONGOING CONVECTION...THE OUTFLOW
   BOUNDARY IS OUTRUNNING THE PARENT CONVECTION OWING TO GENERALLY WEAK
   LOW-LEVEL NELY FLOW EVIDENT IN SHREVEPORT VWP. AS SUCH...ASCENT WILL
   BECOME INCREASINGLY SLOPED AS OPPOSED TO UPRIGHT...AND A WEAKENING
   TREND IN THE ACTIVITY BEHIND THE OUTFLOW BOUNDARY COULD ENSUE.
   HOWEVER...ADDITIONAL ISOLATED STRONG TO SEVERE STORMS COULD DEVELOP
   IN RESPONSE TO CONVERGENCE ALONG THE LEADING EDGE OF THE COLD POOL.
   
   3. BETWEEN THE AFOREMENTIONED TWO AREAS OF ACTIVITY...CONVECTION
   WILL BE MORE ISOLATED IN NATURE INVOF THE AXIS OF A MID-LEVEL RIDGE.
   
   ACROSS THE ENTIRE DISCUSSION AREA...ISOLATED INSTANCES OF DMGG WINDS
   DUE TO WET MICROBURSTS COULD OCCUR WITH THE MORE VIGOROUS CONVECTION
   IN RESPONSE TO STEEP LOW-LEVEL LAPSE RATES OF 8.5 TO 9.5 C/KM
   YIELDING DCAPE VALUES OF 1200 TO 1600 J/KG. MARGINALLY LARGE HAIL
   CANNOT BE RULED OUT GIVEN THE DEGREE OF AMBIENT INSTABILITY...THOUGH
   THE THREAT WILL BE MITIGATED BY MELTING PROCESSES WITHIN THE HOT
   BOUNDARY LAYER.
   
   ..COHEN.. 06/05/2011
   
   
   ATTN...WFO...LCH...SHV...HGX...FWD...CRP...EWX...
   
   LAT...LON   28429648 29209778 30769826 32909743 33599563 33329311
               30849282 29509404 28429648