MESOSCALE DISCUSSION 0272
   NWS STORM PREDICTION CENTER NORMAN OK
   0731 PM CDT FRI MAR 25 2011
   
   AREAS AFFECTED...NCNTRL/NERN TX...SCNTRL/SERN OK...SWRN AR AND NWRN
   LA
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 260031Z - 260200Z
   
   CURRENT POTENTIAL FOR A WW ISSUANCE ACROSS NCNTRL/NERN TX...
   SCNTRL/SERN OK AND EWD TO SWRN AR/NWRN LA REMAINS CONDITIONAL BASED
   ON TSTM DEVELOPMENT.  HOWEVER...GIVEN THE AVAILABLE WARM SECTOR
   INSTABILITY/SHEAR PARAMETERS...STORMS WILL LIKELY BE SEVERE ONCE
   INITIATION OCCURS.  THUS...THIS REGION WILL CONTINUE TO BE MONITORED
   FOR GREATER REFLECTIVITY DEVELOPMENT AND THE NEED FOR A SEVERE
   WEATHER WATCH THIS EVENING.
   
   ...ANALYSIS AND THREATS...
   EARLY EVENING SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE
   LOCATED OVER SOUTH CENTRAL OK /INVOF ADM/ WITH A DRY LINE TRAILING
   SWWD /TO THE NW-W OF DALLAS-FT WORTH METROPLEX/ THROUGH SRN MONTAGUE
   TO STEPHENS COUNTIES TX.  MEANWHILE...A QUASI-STATIONARY BOUNDARY
   EXTENDED ESEWD FROM THE SURFACE LOW THROUGH EXTREME SERN OK TO FAR
   SRN AR AND WEST CENTRAL MS.  LATEST VISIBLE SATELLITE IMAGERY AND
   REGIONAL RADARS INDICATED MORE PERSISTENT AND LIKELY DEEPER CU/TCU
   ALONG THE DRY LINE FROM WISE AND MONTAGUE COUNTIES TX TO LOVE COUNTY
   OK...WITH A SECOND AREA OF GREATER CU FORMATION ALONG AND NORTH OF
   THE STATIONARY FRONT...JUST EAST OF THE SURFACE LOW.
   
   00Z FWD SOUNDING SHOWED A WEAK CAP REMAINS AROUND 700-800 MB WITH
   MLCAPE CLOSE TO 1000 J/KG.  THIS INSTABILITY WHICH WAS SIMILAR
   WITHIN THE WARM SECTOR ACROSS NCNTRL/NERN TX INTO NWRN LA COMBINED
   WITH EFFECTIVE BULK SHEAR AROUND 50 KT IS SUFFICIENT FOR ORGANIZED
   STORMS.  A STRAIGHT HODOGRAPH WITH THIS SOUNDING SUPPORTS SPLITTING
   STORMS.  GIVEN THE FAIRLY SUBSTANTIAL DRY SUB-CLOUD LAYER...STRONG
   WIND GUSTS AND HAIL WOULD BE THE INITIAL PRIMARY THREATS. 
   HOWEVER...ANY STORM THAT CAN TRACK ALONG THE STATIONARY FRONT WOULD
   HAVE A GREATER POTENTIAL TO PRODUCE A TORNADO.
   
   ...STORM INITIATION POTENTIAL...
   GIVEN THE WEAK CAP YET EVIDENT ON THE 00Z FWD SOUNDING AND OVERALL
   WEAK UPPER FORCING ACROSS THIS REGION...STORM INITIATION IS
   UNCERTAIN DURING THE NEXT 1-2 HOURS...WHICH IS MORE CONSISTENT WITH
   THE RECENT RUNS OF THE EXPERIMENTAL HRRR MODEL.  TRENDS IN LOW LEVEL
   FLOW STREAMLINE ANALYSIS INDICATED DIFFLUENT FLOW ACROSS THE
   DISCUSSION AREA WITH WINDS OVER NWRN TX BEGINNING TO BACK IN
   RESPONSE TO PRESSURE FALLS WITH THE LEE TROUGH OVER THE CENTRAL/SRN
   HIGH PLAINS AND MORE VEERED SSWLY WINDS ALONG THE SABINE RIVER. 
   THIS WOULD TEND TO LIMIT LOW LEVEL CONVERGENCE ALONG AFOREMENTIONED
   BOUNDARIES.
   
   THUS...DESPITE THE MORE PERSISTENT CU/TCU DEVELOPMENT...STORM
   INITIATION MAY NOT OCCUR UNTIL AFTER SUNSET ALONG THE RED RIVER
   VALLEY OF NERN TX/SERN OK WHEN THE STRENGTHENING LLJ INTO THIS
   REGION RESULTS IN AN INCREASE OF WAA/ASCENT AND MOISTENING.  THESE
   LATTER FACTORS WOULD SUPPORT BOTH A TORNADO THREAT AND HAIL/DAMAGING
   WINDS.
   
   ..PETERS.. 03/26/2011
   
   
   ATTN...WFO...LZK...SHV...TSA...FWD...OUN...
   
   LAT...LON   33009843 33579774 34149706 34689671 34719614 34409434
               33909252 33119219 32459262 32319420 32689739 33009843