[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 270635
SWODY2
SPC AC 270634

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1234 AM CST SUN NOV 27 2005

VALID 281200Z - 291200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 55 SSE
7R4 MCB TUP BNA 45 SSW LOZ 25 SSW HSS AHN 10 WNW MCN VLD 55 WSW CTY.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SE GLS 20 WSW HEZ
55 S GLH MEM MDH BRL 45 NW LWD DNS 35 ESE BKX AXN ELO 40 NNE GNA.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM MSS UCA BGM DCA RDU
55 ESE CRE.

...THERE IS A SLGT RISK OF SVR TSTMS MON ACROSS THE CNTRL/ERN GULF
STATES AND PARTS OF THE TN VLY....

ALL INDICATIONS ARE THAT STRONG LOW/MID-LEVEL CYCLOGENESIS WILL
PROCEED TODAY ACROSS THE CENTRAL PLAINS.  CYCLONE IS PROGGED TO
REACH PEAK INTENSITY SOMETIME LATE TONIGHT INTO EARLY MONDAY AS IT
LIFTS INTO THE UPPER MISSISSIPPI VALLEY...THEN BEGIN TO OCCLUDE AND
WEAKEN THROUGH THE DAY MONDAY AS IT LIFTS INTO THE UPPER GREAT LAKES
REGION.  THIS IS FORECAST TO OCCUR IN CONJUNCTION WITH NORTHEASTWARD
ACCELERATION OF A SIGNIFICANT MID-LEVEL IMPULSE/JET STREAK...WHICH
WILL BEGIN TO MERGE INTO CYCLONIC REGIME TO THE SOUTH/EAST OF
RETROGRADING POLAR LOW IN THE VICINITY OF HUDSON BAY LATE MONDAY
NIGHT INTO EARLY TUESDAY.

DUE TO RIDGING OFF THE ATLANTIC SEABOARD...BROADER SCALE CENTRAL
U.S. TROUGH WILL BE SLOW TO PROGRESS EAST OF THE PLAINS/MISSISSIPPI
VALLEY REGION. BUT...ANOTHER SIGNIFICANT JET IS PROGGED TO NOSE
THROUGH BASE OF THIS FEATURE OVER THE WESTERN/CENTRAL GULF STATES BY
12Z MONDAY...BEFORE PROPAGATING NORTHEASTWARD TOWARD THE UPPER OHIO
VALLEY MONDAY/MONDAY NIGHT.  THIS IMPULSE WILL HELP MAINTAIN
MODERATELY STRONG SOUTHERLY LOW-LEVEL FLOW OFF THE GULF OF MEXICO
INTO THE CENTRAL/EASTERN GULF STATES AND TENNESSEE VALLEY DURING
THIS FORECAST PERIOD...THOUGH INTENSE PRE-FRONTAL LOW-LEVEL JET CORE
IS PROGGED TO SHIFT NORTHEASTWARD THROUGH THE OHIO VALLEY AND LOWER
GREAT LAKES REGION.

...GULF STATES/TENNESSEE VALLEY...
STRONGER MID/UPPER FORCING AND THERMAL TROUGH STILL APPEAR LIKELY TO
LAG TO THE NORTH/WEST OF SURFACE FRONT AS IT PROGRESSES EAST OF THE
LOWER MISSISSIPPI VALLEY MONDAY...AND POTENTIAL FOR SIGNIFICANT
FRONTAL BAND ACROSS THE GULF STATES IS IN QUESTION.  OF GREATER
CONCERN...HOWEVER...IS THE POTENTIAL FOR CONVECTIVE DEVELOPMENT IN
RATHER MOIST PRE-FRONTAL BOUNDARY LAYER CHARACTERIZED BY MID/UPPER
60S SURFACE DEW POINTS.

DEGREE OF SURFACE HEATING IS STILL UNCERTAIN...AND WARM MID-LEVEL
ENVIRONMENT WITH WEAK LAPSE RATES SHOULD LIMIT CAPE TO MAGNITUDES AT
OR BELOW 1000 J/KG.  BUT...CONFIDENCE IS GROWING THAT LOW-LEVEL WARM
ADVECTION REGIME BENEATH AT LEAST WEAKLY DIFLUENT/DIVERGENT UPPER
FLOW WILL BE SUFFICIENT TO OVERCOME INHIBITION...SUPPORTING
SCATTERED THUNDERSTORMS.

PRE-FRONTAL CONFLUENCE NEAR LOW-LEVEL JET AXIS FROM SOUTH CENTRAL
MISSISSIPPI INTO NORTHERN ALABAMA COULD PROVIDE A FOCUS FOR
DEVELOPMENT BY MID DAY...WITH LOW-LEVEL HODOGRAPHS/DEEP LAYER SHEAR
AND LOW-LEVEL THERMODYNAMIC ENVIRONMENT FAVORABLE FOR TORNADIC
SUPERCELLS.  ACTIVITY IS EXPECTED TO PERSIST THROUGH AT LEAST THE
REMAINDER OF THE DAY...DEVELOPING NORTHWARD/EASTWARD INTO THE
SOUTHERN APPALACHIANS/EASTERN GULF COAST REGION.  FORCING MAY WEAKEN
SUFFICIENTLY AFTER DARK FOR SEVERE THREAT TO DIMINISH BEFORE
BEGINNING TO SPREAD TOWARD SOUTH ATLANTIC COASTAL AREAS.

...OHIO VALLEY INTO NORTHERN/CENTRAL APPALACHIANS...
MODELS CONTINUE TO SUGGEST SURFACE-BASED INVERSION LAYER WILL
PERSIST ACROSS REGION AHEAD OF OCCLUDING SURFACE FRONT...ALONG WHICH
STRONG FORCING IS EXPECTED TO SUPPORT/MAINTAIN CONVECTIVE BAND EAST
OF THE MISSISSIPPI VALLEY INTO THE APPALACHIANS BY MONDAY NIGHT. 
GIVEN FORECAST MAGNITUDE OF LOWER/MID TROPOSPHERIC FLOW /AOA 70
KT/...STABLE LAYER COULD BECOME SHALLOW ENOUGH TO SUPPORT AT LEAST
SPORADIC DAMAGING SURFACE WINDS...ASSOCIATED WITH DOWNWARD MOMENTUM
TRANSFER.

..KERR.. 11/27/2005

...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