Feb-26-2005 0800 UTC Day 2 Convective Outlook
Updated: Sat Feb 26 07:07:32 UTC 2005
Categorical Graphic
20050226 0800 UTC Day 2 Outlook Graphic
Probabilistic Graphic
20050226 0800 UTC Day Probabilitic Graphic
   SPC AC 260703
   
   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0103 AM CST SAT FEB 26 2005
   
   VALID 271200Z - 281200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 15 SE
   GPT 15 NNE GPT 30 NNW CEW 10 ENE AYS 40 ENE CHS.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 SW DMN 50 NNW TUS
   40 SE PRC 30 W ABQ 15 N LVS 25 ENE TCC 15 SE GAG 25 SSW END 15 NE
   LFK 15 ESE ESF 15 E GWO 30 N HSV 30 NNW TYS AHN 40 ESE CLT 35 NNW
   RWI 40 SW HSE.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 NE GLS 40 S CLL 25
   ESE FST 45 SE ELP.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 WSW EUG 45 SSW MFR
   65 SE RBL 20 NNW SCK 25 NW SFO.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL AND ERN GULF
   COAST / FL...
   
   ...SYNOPSIS...
   MODELS FAIRLY CONSISTENT IN EVOLUTION OF UPPER PATTERN...WHICH
   SHOULD FEATURE A MERGING / INTERACTION OF WRN U.S. LOW / TROUGH AND
   STRONG NRN STREAM SHORT-WAVE TROUGH.  THESE FEATURES SHOULD INTERACT
   OVER THE PLAINS / MS VALLEY THIS PERIOD...AS WRN FEATURES MOVE E AND
   NRN STREAM TROUGH DIVES SSEWD. THE RESULT WILL BE A
   HIGHLY-AMPLIFIED FLOW FIELD...WITH A TROUGH APPROACHING THE W
   COAST...A RIDGE OVER THE ROCKIES...A TROUGH OVER THE CENTRAL
   CONUS...AND A RIDGE JUST OFF THE E COAST.
   
   SIGNIFICANT DIFFERENCES EXIST HOWEVER AT THE SURFACE...PRIMARILY
   WITH REGARD TO THE POSITION OF THE MAIN SURFACE LOW ASSOCIATED WITH
   DEEPENING CENTRAL U.S. TROUGH. NAM FORECASTS A LOW INITIALLY OVER
   SWRN LA...WHICH THEN DEEPENS AND MOVES RAPIDLY NEWD WITH TIME WHILE
   REMAINING W OF THE APPALACHIANS THROUGH THE PERIOD.  MEANWHILE...GFS
   PLACES A WEAKER LOW OVER THE N CENTRAL GULF INITIALLY...AND THEN
   MOVES IT ENEWD ACROSS NRN FL AND THEN UP THE SERN U.S. / CAROLINA
   COAST BY THE END OF THE PERIOD.  THE ECMWF IS DIFFERENT YET...WITH
   LOW INITIALLY OVER THE SERN GULF...ACROSS SRN FL BY SUNSET...AND
   THEN WELL OFF THE SERN U.S. COAST BY THE END OF THE PERIOD.
   
   ATTM...WILL LEAN TOWARD THE GFS SOLUTION...WITH LOW EXPECTED TO
   DEVELOP INITIALLY ALONG BAROCLINIC ZONE WHICH WILL LIKELY EXIST OVER
   THE CENTRAL GULF.  WIDESPREAD / WARM ADVECTION PRECIPITATION SHOULD
   EXIST E / NE OF THIS LOW...KEEPING EFFECTIVE BAROCLINIC ZONE OVER
   THE NRN GULF OR PERHAPS JUST ONSHORE.  IN THIS SCENARIO...LOW WOULD
   LIKELY MOVE ACROSS NRN FL...AND THEN UP THE ATLANTIC COAST THROUGH
   THE END OF THE PERIOD.
   
   ...THE SOUTHEAST...
   BASED ON ABOVE EVOLUTION OF SURFACE LOW...MOIST / POTENTIALLY
   UNSTABLE AIRMASS SHOULD SPREAD NEWD INTO COASTAL PORTIONS OF THE
   SOUTHEAST AND ACROSS FL...BENEATH BROAD ZONE OF 50 TO 60 KT WSWLY
   MID-LEVEL FLOW.  INITIAL SEVERE THREAT COULD EXIST WITH WARM FRONT
   AS IT MOVES NWD ACROSS FL / INTO THE GULF COAST REGION DURING THE
   AFTERNOON.  AS INITIAL CONVECTION MOVES NEWD INTO THE MID SOUTH /
   OFF THE SERN U.S. COAST...POTENTIAL WILL EXIST FOR A SECOND EPISODE
   OF SEVERE THREAT ALONG COLD FRONT -- PARTICULARLY ACROSS FL DURING
   THE LATTER HALF OF THE PERIOD. 
   
   STRENGTH OF WIND FIELD AND LIKELIHOOD OF 60S DEWPOINTS SPREADING
   ACROSS FL / THE GULF COAST REGION SUGGESTS THAT ISOLATED TORNADOES
   WILL BE POSSIBLE...ALONG WITH MARGINAL HAIL AND LOCALLY DAMAGING
   WINDS. ATTM...WILL REMAIN CONSERVATIVE WITH SEVERE PROBABILITIES
   DUE TO SIGNIFICANT INCONSISTENCIES IN MODEL DEPICTION OF SURFACE /
   BOUNDARY LAYER OVER THIS REGION.
   
   ...PARTS OF NRN AND CENTRAL TX...
   MODELS HAVE BEEN CONSISTENT IN DEPICTING THE DEVELOPMENT OF A
   CONVECTIVE CLUSTER ACROSS PARTS OF NRN / CENTRAL TX DURING THE
   AFTERNOON...AS COLD AIR ALOFT OVERSPREADS A DIURNALLY HEATED BUT
   MARGINALLY-MOIST BOUNDARY LAYER.  
   
   STORMS WILL LIKELY DEVELOP ACROSS THIS REGION BY
   MID-AFTERNOON...WITH THREAT FOR HAIL AND PERHAPS LOCALLY DAMAGING
   WINDS ENHANCED BY DEEP-LAYER SHEAR SUFFICIENT FOR ORGANIZED
   UPDRAFTS.  THOUGH STORMS SHOULD MOVE ESEWD TOWARD THE COAST...STORMS
   SHOULD WEAKEN AFTER SUNSET.
   
   ..GOSS.. 02/26/2005
   
   ...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 2 OUTLOOK IS SCHEDULED BY 1730Z