Sep-17-2004 1630 UTC Day 1 Convective Outlook
Updated: Fri Sep 17 15:58:07 UTC 2004
Categorical Graphic
20040917 1630 UTC Day 1 Outlook Graphic
Probablistic Tornado Graphic
20040917 1630 UTC Day 1 Tornado Probabilities Graphic
Probablistic Damaging Wind Graphic
20040917 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Probablistic Large Hail Graphic
20040917 1630 UTC Day 1 Large Hail Probabilities Graphic
   SPC AC 171549
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1049 AM CDT FRI SEP 17 2004
   
   VALID 171630Z - 181200Z
   
   THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 W
   ILM 15 N FLO 40 WSW SOP 15 W GSO 35 SE PSK 10 S LYH 40 SSE CHO 15 N
   RIC 40 NNW ORF 10 SSW ORF 15 SW EWN 35 W ILM.
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 SW
   CHS 35 ENE CAE 20 ESE SPA 35 WNW HKY 25 S BLF 35 NE SSU 15 ESE MRB
   20 NE BWI 25 ENE SBY.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 WNW CTY AYS 45 SE
   AGS 40 SSE SPA 20 ENE TYS 40 WNW HTS 25 WNW PIT 30 SE UCA 10 SE PWM.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 ENE CTB 30 NNE SUN
   75 NNW LOL 10 SW EKA.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 SSE CMX 50 WSW IWD
   30 W DLH 50 W HIB 10 ENE RRT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM CZZ 40 SSE DAG 10 WSW
   LAS 55 N IGM 40 ESE SOW 30 SSE ONM 55 WSW TCC 15 NNE DHT 35 SSW MCK
   20 N BUB 15 WSW BKX 30 ESE RWF 30 S RST 15 N COU 25 W HRO 35 SSW PGO
   20 W GGG 10 W GLS.
   
   ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF NC AND SRN VA...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE NC INTO
   THE DELMARVA/CHESAPEAKE...
   
   ...NERN NC ACROSS NC INTO VA...
   SITUATION BECOMING MORE FAVORABLE FOR TORNADOES LATE THIS MORNING
   ACROSS THE AREA.  REMNANTS OF IVAN WILL CONTINUE TO DRIFT NEWD INTO
   CENTRAL VA BY TONIGHT. EAST OF CIRCULATION CENTER...EXTREME SHEAR
   PROFILES ARE IN PLACE WITH 50-60 KT SLY H5 WINDS /40-50 KT AT H85/
   OVERSPREADING ESELY SFC WINDS AND A VERY MOIST WARM SECTOR THIS
   AFTERNOON.  RESULTANT OBSERVED AND FORECAST HODOGRAPHS ARE QUITE
   LARGE AND YIELD SR-HELICITIES IN EXCESS OF 300 M2/S2.  WATER VAPOR
   IMAGERY INDICATES MID/UPPER LEVEL TROUGH BECOMING MORE NEGATIVELY
   TILTED WITH ENHANCED LARGE SCALE ASCENT AHEAD OF PRONOUNCED DRY
   INTRUSION MOVING INTO ERN SC/CENTRAL NC/SWRN VA.  THIS AXIS WILL
   CONTINUE SHIFTING ENEWD THROUGH THE PERIOD.  AHEAD OF THIS LINE OF
   ENHANCED ASCENT...CLEARING/THINNING OVERCAST IS SUPPORTING MODEST
   HEATING WITHIN THE BOUNDARY LAYER. TEMPERATURES AT 15Z ARE ALREADY
   WELL INTO THE 80S FROM ERN SC INTO CENTRAL/ERN NC AND SRN VA WITH
   FURTHER HEATING/DESTABILIZATION EXPECTED THROUGH THE REST OF THE
   DAY.  NET RESULT WILL BE POTENTIAL FOR WIDESPREAD SUPERCELLS AND
   SMALL LINEAR STRUCTURES WELL INTO THE EVENING FROM CENTRAL NC/NERN
   SC NORTHEASTWARD.  TORNADOES AND DAMAGING WINDS ARE LIKELY WHERE
   HEATING WILL BE MAXIMIZED.  THOUGH DESTABILIZATION WILL BE SLOWER TO
   OCCUR AND MORE MARGINAL NWD INTO THE CHESAPEAKE/DELMARVA ...PRESENCE
   OF LOWER TO MID 70F DEW POINTS AND ENHANCED SHEAR SUGGEST A FEW
   SUPERCELLS AND POSSIBLE TORNADOES MAY SPREAD INTO THIS AREA AS WELL.
   
   
   ...CENTRAL PLAINS...
   STRONG LOW LEVEL WAA WITHIN PLUME OF VERY STEEP LAPSE RATES
   CONTINUES TO SUSTAIN STRONG TO SEVERE THUNDERSTORMS...ELEVATED ABOVE
   A RELATIVELY CAPPED BOUNDARY LAYER...THROUGH THE MID MORNING OVER
   ERN KS.  EXPECT THIS ACTIVITY WILL CONTINUE TO UNDERGO WEAKENING
   INTO THE EARLY AFTERNOON WITH CAPPING LIKELY SUPPRESSING DIURNAL 
   STORMS OVER CENTRAL AND WRN KS THIS AFTERNOON. HOWEVER AS LLJ
   INCREASES AFTER DARK...ANOTHER ROUND OF STRONG TO MARGINALLY SEVERE
   THUNDERSTORMS MAY DEVELOP INTO FAR ERN KS/WRN MO AFTER 06Z.
   
   ..EVANS/CROSBIE.. 09/17/2004
   
   ...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 2000Z