MESOSCALE DISCUSSION 0255
   NWS STORM PREDICTION CENTER NORMAN OK
   0625 PM CDT WED MAR 23 2016

   AREAS AFFECTED...PORTIONS OF NORTHERN IN CENTRAL TX

   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

   VALID 232325Z - 240100Z

   PROBABILITY OF WATCH ISSUANCE...80 PERCENT

   SUMMARY...A SEVERE THUNDERSTORM WATCH IS LIKELY ACROSS PARTS OF
   NORTH TX THIS EVENING. LARGE HAIL AND DAMAGING WINDS WILL BE THE
   MAIN CONCERN. THE SOUTHWARD EXTENT OF THE SEVERE THREAT REMAINS
   UNCERTAIN...BUT COULD EXTEND AS FAR SOUTH AS CENTRAL TX INTO THE
   OVERNIGHT HOURS.

   DISCUSSION...THE SEVERE THREAT IS INCREASING ACROSS NORTH TX THIS
   EVENING...THOUGH THE SOUTHWARD EXTENT OF THIS SEVERE THREAT STILL
   REMAINS UNCERTAIN. A TONGUE OF GREATER INSTABILITY CURRENTLY LIES
   ACROSS THE METROPLEX VICINITY WITH MLCAPE VALUES NEAR 1500-2000 J/KG
   AHEAD OF THE SURFACE DRYLINE. LOW LEVEL CONFLUENCE ALONG THE DRYLINE
   COUPLED WITH INCREASING DEEP LAYER FORCING FOR ASCENT AS THE MAIN
   SHORTWAVE IMPULSE EJECTS INTO THE SOUTHERN PLAINS WILL SUPPORT
   FURTHER THUNDERSTORM DEVELOPMENT SOUTH OF THE RED RIVER. STEEP
   MIDLEVEL LAPSE RATES AND EFFECTIVE SHEAR GREATER THAN 45 KT WILL
   SUPPORT ROTATING UPDRAFTS AND LARGE HAIL WILL BE THE MAIN CONCERN AS
   INITIAL STORM MODE SHOULD BE SEMI-DISCRETE SUPERCELLS. WITH EASTWARD
   EXTENT...LOW LEVEL SHEAR WILL BECOME PARALLEL TO THE BOUNDARY. THIS
   MAY RESULT IN A TREND TOWARD LINEAR/BOWING SEGMENTS WITH DAMAGING
   WINDS POSSIBLE IN ADDITION TO LARGE HAIL. 0-1KM SRH WILL INCREASE
   TONIGHT AS THE LOW LEVEL JET STRENGTHENS AND A TORNADO OR TWO CAN
   NOT BE RULED OUT...BUT THE PRIMARY THREAT IS EXPECTED TO BE LARGE
   HAIL AND DAMAGING WINDS. 

   FURTHER SOUTH INTO CENTRAL TX...UNCERTAINTY INCREASES WITH REGARDS
   TO SEVERE POTENTIAL. HI-RES GUIDANCE SUGGESTS STORMS WILL CONTINUE
   TO DEVELOP SOUTHWESTWARD ALONG/AHEAD OF THE DRYLINE. MODERATE
   INSTABILITY IS IN PLACE ACROSS THIS REGION WITH THE AXIS OF HIGHER
   MLCAPE VALUES SPREADING SOUTH/SOUTHWEST FROM THE METROPLEX TOWARD
   AUS AND VICINITY. ADDITIONALLY...AGITATED CU NEAR/JUST BEHIND THE
   DRYLINE WAS NOTED IN VIS SAT FROM NEAR DYS TO SJT. HOWEVER...FORCING
   FOR ASCENT AND LOW LEVEL FLOW IS WEAKER/LESS FAVORABLE ACROSS THIS
   REGION. HIGHER QUALITY MOISTURE IS ALSO LACKING GIVEN VEERED LOW
   LEVEL FLOW ACROSS THE SOUTHWESTERN PORTIONS OF THE MCD AREA. SHOULD
   STORMS DEVELOP THIS FAR SOUTH...LARGE HAIL WILL BE THE PRIMARY
   THREAT.

   ..LEITMAN/HART.. 03/23/2016


   ATTN...WFO...SHV...FWD...OUN...EWX...SJT...

   LAT...LON   32549551 31969592 31049670 30269771 30099871 30169939
               30439972 30859962 31549902 32439834 33439744 33749686
               33819658 33799644 33879611 33819575 33709550 33449534
               33149524 32549551