MESOSCALE DISCUSSION 0341
   NWS STORM PREDICTION CENTER NORMAN OK
   0548 AM CDT MON APR 04 2011
   
   AREAS AFFECTED...PORTIONS CENTRAL THROUGH NE TX...EXTREME SERN
   OK...AR...SERN AND EXTREME S-CENTRAL MO.
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 87...
   
   VALID 041048Z - 041245Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 87
   CONTINUES.
   
   CONVECTION CONTINUES TO INCREASE IN COVERAGE...WITHIN TWO PRIMARY
   NODES THAT MAY ENLARGE/MERGE DURING NEXT FEW HOURS...
   
   1. LARGE/PERSISTENT MULTICELLULAR CLUSTER JUST SW OF WW OVER DFW
   METROPLEX...WITH CONSISTENTLY COLDEST IR CLOUD TOPS.  ACTIVITY HAS
   BEEN RESPONSIBLE FOR A FEW HAIL ESTIMATES UP TO 1.25 INCH DIAMETER
   SINCE 851Z...AND BACKBUILDING SWWD.  CLUSTER IS EXPANDING/MOVING
   NEWD AND BEGINNING TO AFFECT WRN PORTIONS WW AS OF 1030Z....AND
   SHOULD GROW NEWD INTO FAVORABLY MOIST/HIGH-THETAE LOW-LEVEL AIR MASS
   THROUGH MIDMORNING.  WHILE INITIALLY RESPONSIBLE FOR MRGL SVR
   HAIL...SOME POTENTIAL EXISTS FOR COLD-POOL DEVELOPMENT AND
   INCREASING WIND THREAT.
   
   2. CENTRAL/WRN AR...MOVING NEWD TOWARD PORTIONS SRN MO.  EMBEDDED
   TSTM YIELDED MRGL SVR HAIL IN CONWAY COUNTY AR AT 954Z.  THIS
   ACTIVITY SHOULD MOVE/EXPAND NEWD OUT OF WW DURING NEXT 2-3 HOURS. 
   AREAS FARTHER E AND NE INTO MS RIVER LOWLANDS WILL BE MONITORED FOR
   POSSIBLE WW.
   
   SFC COLD FRONT WAS ANALYZED AT 1030Z NEAR LINE FROM STL...UNO...30 S
   FSM...20 N DFW...BWD...SJT...CONTINUING TO MOVE SWD TO SEWD 30-35
   KT.  MODEL FCST SOUNDINGS SUGGEST PRE-STORM ENVIRONMENT AROUND BOTH
   CONVECTIVE PLUMES REMAINS CHARACTERIZED BY STG MLCINH...BUT
   FAVORABLE ELEVATED INSTABILITY...WITH MUCAPE 2000-3000 J/KG OVER AR
   AND 3000-4000 J/KG OVER N TX.  CINH AND SFC GUST POTENTIAL MAY
   INCREASE OVER NEXT FEW HOURS...ESPECIALLY ALONG/AHEAD OF SFC COLD
   FRONT BEFORE RELATED WEDGE OF CAA-RELATED BOUNDARY-LAYER
   STABILIZATION REDUCES DCAPE.
   
   ..EDWARDS.. 04/04/2011
   
   
   ATTN...WFO...PAH...MEG...LZK...SGF...SHV...TSA...FWD...OUN...
   
   LAT...LON   31189626 31099788 31989850 34519514 35859352 36699215
               36879099 36639014 35759010 33119393 31189626