[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 260559
SWODY2
SPC AC 260557

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1157 PM CST FRI NOV 25 2005

VALID 271200Z - 281200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM TUL
CNU MKC LWD OTM MLI MMO 35 NW LAF 10 SSE OWB 20 SE MKL UOX 10 SSE
GWO 45 WNW JAN ELD TXK 20 W DEQ TUL.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 ESE GLS 30 NNE BPT
20 WSW LFK 30 NNE TYR DUA CHK MHK OTG BRD 60 ENE GNA 85 NE MQT 35
ENE APN MTC LUK HSV TOI 50 SSE AAF.

...THERE IS A SLGT RISK OF SVR TSTMS LATE SUN/SUN NIGHT ACROSS PARTS
OF THE MIDDLE/LOWER MISSISSIPPI VALLEY....

MODELS CONTINUE TO INDICATE STRONG UPPER JET...NOW NOSING ACROSS THE
NORTH CENTRAL PACIFIC COAST...WILL SUPPORT AMPLIFYING SHORT WAVE
TROUGH ACROSS THE INTERMOUNTAIN WEST AND CENTRAL ROCKIES BY EARLY
SUNDAY.  THIS SYSTEM IS FORECAST TO PROGRESS EAST OF THE ROCKIES
SUNDAY/SUNDAY NIGHT...ACCOMPANIED BY SIGNIFICANT LOW/MID- LEVEL
CYCLOGENESIS.  CONSIDERABLE VARIABILITY EXISTS CONCERNING DETAILS OF
THIS EVOLUTION.  HOWEVER...AFTER LOWEST SURFACE PRESSURES NEAR
CYCLONE CENTER LEVEL OFF LATE TODAY/TONIGHT ACROSS THE CENTRAL
PLAINS...IT APPEARS ADDITIONAL RAPID DEEPENING MAY NOT COMMENCE
UNTIL VERY LATE SUNDAY AFTERNOON...MORE LIKELY SUNDAY NIGHT...AS LOW
LIFTS TOWARD THE UPPER MISSISSIPPI VALLEY.  THIS IS FORECAST TO
OCCUR AS A SIGNIFICANT IMPULSE/JET STREAK ROTATES AROUND
SOUTHERN/EASTERN PERIPHERY OF DEVELOPING MID-LEVEL CIRCULATION.

MODIFICATION OF LOW-LEVEL ENVIRONMENT EAST OF THE ROCKIES ALREADY
APPEARS UNDERWAY AS CENTER OF BROAD POLAR LOW CONTINUES TO RETREAT
NORTHWARD THROUGH THE EASTERN CANADIAN PROVINCES.  BOUNDARY LAYER IS
SLOWLY MOISTENING FROM THE WESTERN GULF OF MEXICO INTO SOUTHEAST
TEXAS...AND AT LEAST LIMITED RETURN FLOW /CHARACTERIZED BY MID 50S
TO LOWER 60S SURFACE DEW POINTS/ IS LIKELY BY LATE SUNDAY AFTERNOON
INTO WARM SECTOR OF CYCLONE ACROSS THE MIDDLE MISSISSIPPI VALLEY.

CONVECTION MAY BE ONGOING EARLY SUNDAY EAST OF THE LOWER MISSISSIPPI
VALLEY IN RESPONSE TO WEAKENING SOUTHERN STREAM IMPULSE EMANATING
FROM THE MEXICAN PLATEAU.  THIS ACTIVITY SEEMS LIKELY TO DIMINISH
DURING THE DAY AS UPPER FEATURE PROGRESSES EASTWARD AND WEAKENS IN
AMPLIFYING BROADER SCALE UPPER RIDGE OVER THE SOUTH ATLANTIC COAST
STATES.

IN ITS WAKE...NORTHWARD RETURNING MOISTURE IS EXPECTED TO BE
ACCOMPANIED BY CONSIDERABLE LOW CLOUD COVER FROM THE UPPER TEXAS/
LOUISIANA COAST THROUGH MUCH OF THE MISSISSIPPI VALLEY.  THIS WILL
LIMIT SURFACE HEATING AND MAGNITUDE OF POTENTIAL DESTABILIZATION. 
COMPLICATING MATTERS FURTHER...MODELS SUGGEST A TENDENCY FOR
MID-LEVEL COLD POOL TO LAG TO THE WEST OF THE SURFACE COLD
FRONT...WHICH IS PROGGED TO SURGE THROUGH THE SOUTH CENTRAL PLAINS
BY SUNDAY AFTERNOON.  DESPITE UNCERTAINTIES...LIKELIHOOD OF AT LEAST
WEAK DESTABILIZATION AND STRONG FORCING/SHEAR ASSOCIATED WITH 100 KT
MID-LEVEL JET SUPPORTS RISK OF SEVERE STORMS...MAINLY ACROSS THE
OZARK PLATEAU THROUGH THE MIDDLE MISSISSIPPI VALLEY SUNDAY NIGHT.

...MISSISSIPPI VALLEY...
INITIATION OF VIGOROUS CONVECTIVE DEVELOPMENT MAY OCCUR PRIOR TO
28/00Z...AHEAD OF COLD FRONT NEAR THE KANSAS/MISSOURI BORDER. 
HOWEVER...MODELS SUGGEST STRONGEST FORCING WILL DEVELOP ALONG THE
FRONT AFTER 28/00Z...FROM PARTS OF WESTERN ARKANSAS THROUGH CENTRAL
MISSOURI...WHERE RAPID EVOLUTION OF A SQUALL LINE MAY OCCUR DESPITE
CAPE ONLY ON THE ORDER OF 500 TO 1000 J/KG.

TORNADO POTENTIAL IS UNCERTAIN...DUE TO POSSIBILITY OF AT LEAST
SHALLOW STABLE LAYER NEAR SURFACE.  HOWEVER...SHEAR BENEATH
SOUTHERLY LOW-LEVEL JET /PROGGED TO STRENGTHEN IN EXCESS OF 70 KT
SUNDAY EVENING/ WILL BE MORE THAN FAVORABLE FOR SUPERCELLS WITH
TORNADOES.  OTHERWISE...CONFIDENCE IS GROWING IN DAMAGING WIND
POTENTIAL ALONG SQUALL LINE...WHICH IS EXPECTED TO RAPIDLY ADVANCE
EAST OF THE MISSISSIPPI RIVER BEFORE DIMINISHING BY DAYBREAK MONDAY.

NEW CONVECTIVE DEVELOPMENT COULD OCCUR LATE SUNDAY NIGHT THROUGH
PARTS OF THE LOWER MISSISSIPPI VALLEY. HOWEVER...STRONGER MID-LEVEL
FORCING IS PROGGED TO LAG WELL BEHIND FRONT AT THAT TIME...AND
ACTIVITY MAY BE BASED ABOVE/JUST TO THE WEST OF SURFACE COLD
FRONT...LIMITING SEVERE THREAT.

..KERR.. 11/26/2005

...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