Nov 28, 2005 1630 UTC Day 1 Convective Outlook
Updated: Mon Nov 28 16:42:13 UTC 2005
Probabilistic to Categorical Outlook Conversion Table in HTML, or PDF formats.
Public Severe Weather Outlook

The SPC is forecasting an outbreak of severe thunderstorms today and tonight across portions of the United States. This is an extremely dangerous situation. Please read the latest public statement about this event.

Categorical Graphic
20051128 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20051128 1630 UTC Day 1 Tornado Probabilities Graphic
Probabilistic Damaging Wind Graphic
20051128 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Probabilistic Large Hail Graphic
20051128 1630 UTC Day 1 Large Hail Probabilities Graphic
   SPC AC 281618
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1018 AM CST MON NOV 28 2005
   
   VALID 281630Z - 291200Z
   
   THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 SSW
   AUO 10 NNW GZH 50 SSE MEI 25 NE MEI 10 S CBM 15 WSW MSL 45 N HSV 10
   NNE CHA 15 W ATL 25 SSW AUO.
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 60 SSE
   HUM 20 S TUP 20 NW HOP 35 WNW IND 30 SSE SBN 35 SW JXN 50 WNW CLE 10
   NNE ZZV 25 WNW CRW 20 NNW AVL 50 NE MGR 45 WNW CTY.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 NNE ROC 35 SSW ROC
   20 E AOO 15 W RIC GSB 35 SE ILM ...CONT... 60 SSW HUM 40 NE JAN 15
   NNW PAH 15 S DEC 30 E MLI 25 NNW ALO 40 W EAU 75 NNE CMX.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 NE VRB 35 WSW APF.
   
   ...THERE IS A MDT RISK OF SVR TSTMS MUCH OF AL PARTS OF MID TN AND
   NWRN GA...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL GULF COAST NWD
   TO THE SRN GREAT LAKES...
   
   ...SYNOPSIS...
   INTENSE NEARLY VERTICALLY STACKED CYCLONE MOVING SLOWLY NEWD ACROSS
   IA TODAY REACHING INTO NRN WI BY TUE AM.  VERY STRONG MID/UPPER
   LEVEL JET EXTENDING FROM LOWER MS VALLEY ACROSS LOWER OH VALLEY WILL
   SHIFT N AND E THIS AFTERNOON MAINTAINING A VERY FAVORABLE SHEAR
   ENVIRONMENT FOR SUPERCELLS IN THE WARM SECTOR.
   
   PRE-FRONTAL INSTABILITY LINE CURRENTLY FROM WRN IND SSWWD INTO ERN
   MS PRECEDES THE COLD FRONT WHICH EXTENDS FROM THE IA SURFACE LOW SWD
   VICINITY STL AND THEN TO SRN LA.
   
   ...AL INTO MID TN AND WRN GA...
   WARM SECTOR AHEAD OF PRE-FRONTAL SQUALL LINE CHARACTERIZED BY A VERY
   MOIST AND INCREASINGLY UNSTABLE AIRMASS...MUCAPES UPWARDS TO  2000
   J/K SRN AL... AS SURFACE HEATING PUSHES THE TEMPS INTO THE MID 70S
   AT 15Z WITH DEWPOINTS RISING THRU THE MID/UPPER 60S.  GIVEN THE
   SFC-1KM SHEAR OF 30-40KT AND HELICITIES FROM 400-500 M2/S2 AS NOTED
   ON THE BMX VAD WINDS AND LITTLE REMAINING CIN...CONDITIONS ARE
   FAVORABLE FOR RAPID DEVELOPMENT OF TORNADIC SUPERCELLS BY EARLY THIS
   AFTERNOON AHEAD OF INSTABILITY LINE.  POTENTIAL THIS AFTERNOON WILL
   EXIST FOR STRONG TORNADOES ACROSS WARM SECTOR IN AL INTO WRN GA AND
   MIDDLE TN.
   
   ADDITIONALLY SEVERE STORMS WILL ALSO DEVELOP IN THE CONVERGENCE
   ALONG/AHEAD OF SQUALL LINE BY EARLY/MID AFTERNOON.  MORE
   UNIDIRECTIONAL SHEAR WOULD FAVOR BOWS/LINE SEGMENTS WITH THESE
   STORMS AND GIVEN VERY STRONG FLOW...WIND DAMAGE WILL BE PRIMARY
   THREAT.
   
   ...OH VALLEY...
   
   ALTHOUGH LESS INSTABILITY IS AVAILABLE IN WARM SECTOR ACROSS OH
   VALLEY...THE VERY STRONG SHEAR COUPLED WITH MUCAPES UPWARD TO 500
   J/KG MORE THAN SUFFICIENT FOR SEVERE THUNDERSTORM DEVELOPMENT.
   
   THE LIMITED SURFACE HEATING WILL REQUIRE THE STRONG QG FORCING UNDER
   THE INTENSE UPPER JET TO PROMOTE SURFACE BASED THUNDERSTORM 
   DEVELOPMENT DURING THE AFTERNOON. PRIMARY MODE WILL BE LINEAR WITH
   BOWS/LINE SEGMENTS. WIND DAMAGE WILL BE PRIMARY THREAT WITH
   POTENTIAL OF TORNADOES ASSOCIATED WITH BOW VORTICES.
   
   BY EVENING AN EXTENSIVE SQUALL LINE WILL BE MOVING EWD ACROSS ERN OH
   VALLEY SWD INTO ERN AL/GA WITH THE SEVERE THREAT CONTINUING BUT
   GRADUALLY DECREASING AFTER SUNSET AS AIR MASS BEGINS TO STABILIZE.
   
   ..HALES/GUYER.. 11/28/2005
   
   ...NOTICE...
   THE STATION RELATIVE POINTS IN THIS PRODUCT WILL BE
   DISCONTINUED ON 14 FEBRUARY 2006 BUT WILL REMAIN AVAILABLE
   IN THE FOLLOWING PRODUCTS:
   
      WMO HEADER:       AWIPS ID:
      WUUS01            PTSDY1
      WUUS02            PTSDY2
      WUUS03            PTSDY3
   
   A SERVICE CHANGE NOTICE ...SCN05-39... PROVIDES DETAILS
   ON THE TRANSITION. FOR ADDITIONAL DETAILS SEE THE FOLLOWING
   WEB ADDRESS USING LOWER CASE LETTERS:
   WWW.NWS.NOAA.GOV/OM/NOTIF.HTM
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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