SPC AC 011249
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0649 AM CST SUN FEB 01 2004
   
   VALID 011300Z - 021200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 ENE
   CRP 30 E SAT 25 WNW AUS 40 WNW TPL ACT 45 E ACT 45 N HOU LCH 30 SSE
   LCH.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 ENE CRP SAT BWD
   CDS 30 ESE GAG BVO FYV HOT ELD MLU HEZ BTR 35 SW HUM.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 N 4BK 35 ESE UKI
   25 SSW SJC.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 SSE FMY 35 ESE FMY
   20 NNE AGR 55 WNW ORL GNV 20 SSE JAX.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS PARTS OF
   SOUTHEAST TEXAS....
   
   A SPLIT PERSISTS IN THE LARGE-SCALE UPPER FLOW PATTERN OVER THE EAST
   CENTRAL PACIFIC.  THE DOWNSTREAM NORTHERN BRANCH...WHICH EXTENDS
   EASTWARD ACROSS THE U.S...IS NOW MORE PROMINENT...WITH A COUPLE OF
   EMBEDDED HIGH AMPLITUDE...PROGRESSIVE SHORT WAVE TROUGHS.  LATEST
   WATER VAPOR IMAGERY INDICATES LEAD TROUGH IS BEGINNING TO SHIFT EAST
   OF THE CENTRAL/SOUTHERN ROCKIES INTO THE HIGH PLAINS.  MODELS
   SUGGEST THIS FEATURE WILL GRADUALLY TAKE ON A NEGATIVE TILT...AND
   CONTINUE SLOWLY ACROSS THE CENTRAL/SOUTHERN PLAINS DURING THIS
   FORECAST PERIOD...AS ANOTHER VIGOROUS SHORT WAVE TROUGH APPROACHES
   THE PACIFIC COAST.
   
   DESPITE STRENGTH OF MID/UPPER FORCING...WITH LOWER LEVELS EAST OF
   THE ROCKIES STILL ONLY SLOWLY RECOVERING FROM RECENT INTRUSION OF
   CONTINENTAL POLAR/ARCTIC AIR...MODELS INDICATE THAT SURFACE
   CYCLOGENESIS OVER THE SOUTH CENTRAL PLAINS WILL REMAIN RELATIVELY
   WEAK.  COUPLED WITH STABILIZATION OF THE WESTERN GULF OF MEXICO IN
   THE WAKE OF A SHORT WAVE TROUGH...WHICH CONTINUES TO DEAMPLIFY AS IT
   LIFTS ACROSS THE EASTERN GULF/SOUTH ATLANTIC COAST STATES...
   CONVECTIVE POTENTIAL ACROSS THE SOUTH CENTRAL U.S. IS EXPECTED TO
   REMAIN LIMITED TODAY/TONIGHT.
   
   ...WESTERN GULF INTO SOUTHERN PLAINS/LOWER MISSISSIPPI VALLEY... 
   MAGNITUDE OF DESTABILIZATION DURING THE DAYTIME HOURS IS PRIMARY
   UNCERTAINTY WITH REGARD TO EXTENT OF SEVERE THREAT ACROSS
   CENTRAL/EASTERN TEXAS. SURFACE DEW POINTS ACROSS THE COASTAL PLAINS
   OF TEXAS ARE CURRENTLY ONLY IN THE UPPER 40S/LOWER 50S...WITH MID/
   UPPER 50S EVIDENT IN THE OFFSHORE BUOYS.  BOTH AVN/ETA SUGGEST WEAK
   MOISTENING WILL OCCUR INLAND THROUGH THE DAY...WITH DEW POINTS
   RANGING FROM THE LOWER 50S...ACROSS NORTHEAST TEXAS...TO THE UPPER
   50S...IN AREAS NORTH OF CORPUS CHRISTI/EAST OF SAN ANTONIO.
   
   EVEN WITH THESE DEW POINTS...ETA POINT FORECAST SOUNDINGS WITH THE
   KAIN-FRITSCH CONVECTIVE PARAMETERIZATION INDICATE MEAN MIXED LAYER
   CAPE IN EXCESS OF 500 J/KG BY AFTERNOON ACROSS PARTS OF EAST TEXAS
   ...WITH MOST UNSTABLE CAPE UP TO 1000 J/KG.  THIS IS PROGGED TO
   DEVELOP IN RESPONSE TO COMBINATION OF LOW-LEVEL WARMING/MID-LEVEL
   COOLING AS UPPER TROUGH ROTATES ACROSS TEXAS THIS AFTERNOON. 
   
   AVN/GFS IS SIGNIFICANTLY WEAKER WITH DESTABILIZATION...PRIMARILY DUE
   TO MUCH WEAKER SURFACE HEATING PROGGED THAN THE ETA-KF.  ETA-KF
   APPEARS MORE LIKELY TO COME CLOSER TO VERIFYING...AT LEAST FROM THE
   MIDDLE TEXAS COAST INTO THE VICTORIA AND AUSTIN AREAS...WHERE
   VIGOROUS CONVECTIVE DEVELOPMENT APPEARS POSSIBLE BY EARLY AFTERNOON
   IN ZONE OF ENHANCED LOW-LEVEL WARM ADVECTION.  EMBEDDED IN STRONGLY
   SHEARED ENVIRONMENT ALONG SOUTHERLY LOW-LEVEL JET AXIS...A FEW
   SEVERE THUNDERSTORMS ARE EXPECTED.  ISOLATED SUPERCELLS ARE
   POSSIBLE...THOUGH MARGINAL SEVERE HAIL APPEARS LIKELY TO BE PRIMARY
   THREAT.  
   
   ACTIVITY IS EXPECTED TO SPREAD WITH STRONGER FORCING FOR UPWARD
   VERTICAL MOTION...IN EXIT REGION OF CYCLONIC MID/UPPER JET
   STREAK...INTO NORTHEAST TEXAS BY LATE AFTERNOON.  HOWEVER...IN
   COOLER/LESS MOIST THERMODYNAMIC ENVIRONMENT...WEAKER DESTABILIZATION
   IS EXPECTED TO RESULT IN DIMINISHING INTENSITY.
   
   MODELS SUGGEST PROGRESSION OF ANOTHER JET STREAK THROUGH BASE OF
   UPPER TROUGH WILL SUPPORT AN INCREASE IN LARGE-SCALE UPWARD VERTICAL
   MOTION ALONG WEAK WARM FRONT NEAR THE UPPER TEXAS/ SOUTHWEST
   LOUISIANA COAST THIS EVENING.  THOUGH HODOGRAPHS WILL BECOME
   FAVORABLE FOR TORNADIC SUPERCELLS...WEAK MID-LEVEL LAPSE RATES WILL
   TEND TO LIMIT INSTABILITY OVER INLAND AREAS...AND MOST VIGOROUS
   STORMS MAY REMAIN OFFSHORE.
   
   ...FLORIDA...
   POTENTIAL FOR THUNDERSTORM ACTIVITY IS DIMINISHING.  HOWEVER... WEAK
   UPPER TROUGHING/WEAK MID-LEVEL CAP OVER THE NORTHERN FLORIDA
   PENINSULA MAY ALLOW A STORM OR TWO TO DEVELOP TODAY...MAINLY NEAR
   FRONTAL BOUNDARY ALONG THE COAST NEAR/NORTH OF MELBOURNE.
   
   ...NORTHERN CALIFORNIA COAST...
   WITH NEXT COLD UPPER TROUGH...A FEW THUNDERSTORMS MAY APPROACH
   COASTAL AREAS BY 02/12Z...BUT ACTIVITY IS EXPECTED TO GENERALLY
   REMAIN OFFSHORE THROUGH THIS PERIOD.
   
   ..KERR.. 02/01/2004
   
   ...NOTICE...
   FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
   LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
   GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
   HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
   INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
   
   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED FOR 1630Z