Categorical Graphic
Probabilistic Tornado Graphic
Probabilistic Damaging Wind Graphic
Probabilistic Large Hail Graphic

   SPC AC 171616
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1016 AM CST SUN FEB 17 2008
   
   VALID 171630Z - 181200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CENTRAL
   AND NERN GULF COAST REGION...
   
   ...SYNOPSIS...
   LONGWAVE TROUGH WILL CONTINUE TO BE CARVED OUT OVER MUCH OF THE
   CENTRAL U.S. TODAY WITH UPPER LOW BECOMING LESS DEFINED AS IT LIFTS
   ACROSS THE MID MS RIVER VALLEY WITH SECONDARY ENERGY DIGGING OVER
   THE CENTRAL PLAINS.  BROAD REGION OF ENHANCED MID AND UPPER LEVEL
   SWLY WINDS WILL PERSIST AHEAD OF THE LONGWAVE TROUGH WITH JET AXES
   EXTENDING FROM THE LOWER MS RIVER VALLEY INTO THE UPPER OH RIVER
   VALLEY/APPALACHIANS THROUGH THE PERIOD.  THIS WILL LEAVE VERY STRONG
   UPPER WINDS /IN EXCESS OF 100 KT AT H25/ ACROSS THE GULF COAST
   STATES WHERE MARGINAL DESTABILIZATION WILL OCCUR TODAY. 
   ELSEWHERE...INSTABILITY WILL LIKELY REMAIN QUITE WEAK AS SURFACE
   FRONT OUTRUNS NWD TRANSPORT OF GULF MOISTURE NORTH OF THE
   CENTRAL/NERN GULF COAST REGION AND GREATLY LIMIT SEVERITY OF
   EXPECTED THUNDERSTORMS THROUGH THE PERIOD.  HAVE ADJUSTED/LOWERED
   SEVERE PROBABILITIES ACCORDINGLY AND EXPECT MAINLY LOW-END THREAT OF
   STRONG/DAMAGING WINDS ACROSS THESE AREAS.  JUST OFF THE NC COAST
   EARLY MONDAY MORNING...INCREASED ASCENT WILL OVERSPREAD THE GULF
   STREAM AND SLY LOW LEVEL FLOW WILL BRING 60F+ SURFACE DEW POINTS
   INTO COASTAL NC.  HOWEVER...FORECAST SOUNDINGS SUGGEST THIS AREA
   WILL REMAIN SLIGHTLY CAPPED TO SURFACE BASED PARCELS AND WILL KEEP
   LOW TORNADO/WIND PROBABILITIES ACCORDINGLY.
   
   ...CENTRAL/NERN GULF COAST STATES...
   REFERENCE SWOMCD 256 JUST ISSUED FOR THIS REGION.  EXPECT A GENERAL
   INCREASE IN THUNDERSTORM COVERAGE/INTENSITY FROM SERN LA INTO
   CENTRAL AL OVER THE NEXT FEW HOURS.  FORECAST SOUNDINGS SUGGEST AS
   REGION WARMS INTO THE LOWER 70S AND SURFACE DEW POINTS INCREASE
   THROUGH THE MID 60S...CAP WILL WEAKEN SUFFICIENTLY FOR STORMS TO TAP
   MODEST SBCAPE AND ASSOCIATED ENHANCED LOW LEVEL SHEAR ACROSS THE
   REGION.  THIS IS EXPECTED TO INCREASE UPDRAFT INTENSITIES WITH
   STRONG/SEVERE STORMS SPREADING ENEWD ACROSS CENTRAL/SRN AL AND INTO
   SWRN GA/WRN FL PANHANDLE THROUGH THE LATE AFTERNOON.  PRIMARY
   THREATS WILL BE FROM DAMAGING WINDS AND ISOLATED TORNADOES WITH
   STRONG SHEAR SUPPORTING SUPERCELLS AND SMALL BOWING STRUCTURES.  AS
   BROKEN LINE OF STORMS SPREADS EWD ACROSS SRN APPALACHIANS/GA DURING
   LATE TODAY/THIS EVENING...EXPECT STORMS WILL STRUGGLE TO ROOT INTO
   THE BOUNDARY LAYER AND OVERALL SEVERE THREAT SHOULD WANE WITH EWD
   EXTENT.
   
   ..EVANS.. 02/17/2008
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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