MESOSCALE DISCUSSION 0696
   NWS STORM PREDICTION CENTER NORMAN OK
   0141 PM CDT FRI MAY 06 2011
   
   AREAS AFFECTED...PORTIONS OF SWRN TX
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 061841Z - 062045Z
   
   WHILE AN ISOLATED SVR STORM OR TWO WILL BE POSSIBLE THIS AFTERNOON
   OVER PORTIONS OF SWRN TX...THE ISSUANCE OF A WW IS UNLIKELY.
   
   THE INFLUX OF A PARTIALLY MODIFIED GULF AIR MASS ACROSS PORTIONS OF
   SRN TX IS SUPPORTING A FAIRLY WELL-DEFINED MOISTURE GRADIENT ARCING
   ENE TO WSW ACROSS THE EDWARDS PLATEAU TOWARD A WEAK MESOLOW 10 W OF
   6R6...AND EXTENDING FARTHER SOUTH ALONG THE E-FACING SLOPES OF THE
   NRN MEXICO MOUNTAINS. THIS AIR MASS IS CHARACTERIZED BY SFC
   DEWPOINTS IN THE UPPER 50S TO LOWER 60S...CAPPED BY AN ELEVATED
   MIXED LAYER FEATURING MID-LEVEL LAPSE RATES FROM 8.5 TO 9 C/KM PER
   12Z OBSERVED SOUNDINGS. THESE FACTORS ARE SUPPORTING MODERATE
   INSTABILITY /MLCAPE VALUES OF 1000 TO 2000 J PER KG/ INVOF THE MOIST
   AXIS.
   
   CONVECTIVE INHIBITION HAS BEEN SLOW TO ERODE THUS FAR WITHIN 60 NM
   NE OF THE RIO GRANDE RIVER OVER THE EDWARDS PLATEAU...OWING TO
   PERSISTENT STRATUS SINCE THE MORNING HOURS. HOWEVER...GREATER
   INSOLATION FOUND NEAR A SFC CONFLUENCE AXIS EXTENDING NNW OF THE
   AFOREMENTIONED MESOLOW IS SUPPORTING LESS CINH OVER THE NWRN
   PERIPHERY OF THE MOIST AXIS -- I.E. OVER ERN PORTIONS OF THE EDWARDS
   PLATEAU INTO THE TRANS-PECOS REGION. AS SUCH...RECENT VISIBLE
   SATELLITE IMAGERY DEPICTS THE DEVELOPMENT OF A CU FIELD AROUND AND
   JUST W OF FORT STOCKTON.
   
   THERE WILL BE THE POTENTIAL FOR ONE OR TWO DEEPER CONVECTIVE PLUMES
   TO EVOLVE FROM THE CU FIELD BETWEEN 20Z AND 22Z...AS AFFIRMED BY
   RECENT CONVECTION-ALLOWING MODEL GUIDANCE. ANY CONVECTION WILL
   LIKELY BE HIGHER BASED INITIALLY WITH THE POTENTIAL FOR GUSTY WINDS.
   HOWEVER...AS THE ACTIVITY IS STEERED EWD OVER THE EDWARDS PLATEAU
   AND INTERACTS WITH THE RICHER LOW-LEVEL MOISTURE AND GREATER
   INSTABILITY...IT WILL HAVE THE POTENTIAL TO STRENGTHEN AND POSSIBLY
   BECOME SEVERE POSING THE THREAT FOR DMGG WINDS AND LARGE HAIL. WHILE
   THIS POTENTIAL WILL BE SUPPORTED BY NOTABLE DIRECTIONAL SHEAR IN THE
   0-3-KM-AGL LAYER PER AREA PROFILER DATA...THE RELATIVELY WEAK
   MID-LEVEL FLOW WILL LIKELY TEMPER THE OVERALL SEVERE THREAT.
   ADDITIONALLY...WITHOUT ANY SUBSTANTIAL DEEP-LAYER FORCING...THE
   COVERAGE OF SVR STORMS IS EXPECTED TO BE ISOLATED...AT MOST. AS
   SUCH...A WW IS UNLIKELY.
   
   ..COHEN.. 05/06/2011
   
   
   ATTN...WFO...EWX...SJT...MAF...
   
   LAT...LON   29710172 29770240 30310299 30900330 31630307 32040210
               32200079 31690008 30790009 30010025 29540070 29470124
               29710172