SPC AC 251605
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1105 AM CDT MON APR 25 2005
   
   VALID 251630Z - 261200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 ENE
   CRP 30 W VCT 15 SSE AUS 35 NW ACT 25 WNW OKC 25 WSW BVO 40 SSW JLN
   45 WNW HOT 30 W GLH 25 ENE JAN 45 WSW SEM 30 SSE SEM 35 SSW TOI 25
   WNW PFN.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 SSE DRT 30 ESE JCT
   20 NNW BWD 30 W ABI 40 NW GDP 25 SW DMN 20 NE TUS 55 SSW PRC 55 SE
   TPH 45 N SVE 30 N LMT 40 SSE RDM 35 N BNO 40 ENE OWY 15 SSW SLC 35
   NE VEL 60 SW LAR 15 ESE DEN 30 NW LHX 40 SW DHT 10 WSW AMA 65 SW GAG
   15 SE ICT 20 S MHK 10 SSW CNK 35 W LNK 15 SSW LSE 20 NE LNR 25 WNW
   RFD 15 ENE SPI 25 NNW SLO 25 ESE MVN 15 SW OWB 20 WNW RMG 10 SW LGC
   10 SSE PFN.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS SRN PLAINS AND LOWER MS
   VALLEY...
   
   ...SRN PLAINS/LOWER MS VALLEY...
   
   SRN STREAM S/WV TROUGH CURRENTLY MOVING EWD ACROSS WRN TX BECOMES
   ABSORBED BY THE CIRCULATION AROUND THE LARGE NEARLY STATIONARY COLD
   UPPER LOW OVER THE WRN GREAT LAKES.  THUS BY TONIGHT STRONG POLAR
   JET WILL EXTEND FROM CENTRAL TX TO SERN STATES. THIS WILL PUT IN
   PLACE A FAVORABLE SHEAR ENVIRONMENT FOR ORGANIZED/SEVERE
   THUNDERSTORMS FROM SRN PLAINS TO LOWER MS VALLEY.  COUPLED WITH
   STRONG SHEAR THE RELATIVELY COLD LAPSE RATES WILL SPREAD AN ELEVATED
   MIX LAYER ACROSS SRN PLAINS TODAY ENHANCING INSTABILITY POTENTIAL.
   
   BOTH THE COVERAGE AND INTENSITY OF SEVERE THUNDERSTORMS WILL DEPEND
   PRIMARILY ON BOTH THE RETURNING LOW LEVEL MOISTURE AHEAD OF THE
   SURFACE LOW NOW LOCATED OVER THE TX PANHANDLE AND A DEVELOPING DRY
   LINE WHICH WILL BE MOVING EWD ACROSS OK/TX THIS AFTERNOON.
   
   THE ELEVATED OVERNIGHT CONVECTION SRN PLAINS SUPPORTED BY ONGOING
   MOISTURE RETURN AND WARM ADVECTION SHOULD SHIFT EWD THIS AFTERNOON
   AND ALLOW GOOD SURFACE HEATING TO TAKE PLACE ACROSS WRN OK INTO
   CENTRAL TX.  SURFACE LOW DEVELOPS SE AND THEN EWD ALONG RED RIVER
   VALLEY THIS AFTERNOON AND DRY LINE SETS UP FROM CENTRAL OK SSWWD
   ACROSS NCENTRAL TX TO NEAR DRT. AIR MASS WILL BECOME MODERATELY
   UNSTABLE WITH MLCAPES RANGING FROM 1000 J/KG ERN OK UPWARDS TO 2000
   J/KG NRN TX AHEAD OF DRY LINE WHERE DEWPOINTS WILL CLIMB TO NEAR
   60F.
   
   SURFACE INITIATION OF SEVERE THUNDERSTORMS WILL OCCUR BY MID
   AFTERNOON ALONG AND E OF DRY LINE WITH THE 50-60 KT OF DEEP LAYER
   SHEAR COUPLED WITH THE FAVORABLE THERMODYNAMIC PROFILES SUPPORTING
   SUPERCELL DEVELOPMENT. WHILE LARGE HAIL WILL BE THE DOMINANT THREAT
    ...ISOLATED TORNADOES ARE ALSO LIKELY GIVEN THE
   SHEAR...PARTICULARLY N TX WHERE SHEAR WILL BE STRONGER.  PARTS OF
   THIS AREA MAY NEED TO BE UPGRADED IN AFTERNOON OUTLOOK IF MOISTURE
   RETURN AND INSTABILITY IS SUFFICIENT.
   
   STORMS SHOULD THEN DEVELOP S/SEWD THRU ERN TX INTO THE EVENING AS
   CAP WEAKENS FURTHER. ADDITIONALLY STORMS OVER SRN OK/NRN TX ARE
   LIKELY TO EVOLVE INTO A MCS/SQUALL LINE AND CONTINUE EWD OVERNIGHT
   ACROSS LOWER MS VALLEY.  AGAIN AMOUNT OF SEVERE OVERNIGHT WILL BE
   DEPENDENT ON THE DEGREE OF DESTABILIZATION THAT CAN OCCUR AS SHEAR
   WILL REMAIN VERY FAVORABLE FOR ORGANIZED/SEVERE STORMS.  WHILE
   DAMAGING WINDS/HAIL WILL BE PRIMARY THREAT...ISOLATED TORNADOES WILL
   BE POSSIBLE ASSOCIATED WITH ANY SUPERCELL THAT CAN DEVELOP IN THE
   AREA OF STRONGEST INSTABILITY...PARTICULARLY SRN MS/LA.
   
   ..HALES/BANACOS.. 04/25/2005
   
   ...NOTICE...
   THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
   SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
   WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
   IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
   CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
   WILL PROVIDE DETAILS ON THE TRANSITION.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z