[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 210537
SWODY1
SPC AC 210535

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1235 AM CDT FRI OCT 21 2005

VALID 211200Z - 221200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 SE GPT 50 ESE MEI
25 SSW EVV 20 NW BMG 35 SSW FDY 15 WSW AOO 25 ESE ACY.

...NO SVR TSTM AREAS FORECAST...

SOUTHERN BRANCH CLOSED LOW IS NOW RAPIDLY WEAKENING IN CONFLUENT
UPPER FLOW REGIME ACROSS THE LOWER OHIO VALLEY.  THIS IS IN WAKE OF
LARGE EASTERN CANADIAN VORTEX...WHICH IS ALREADY BEGINNING TO SHIFT
EAST OF THE CANADIAN MARITIMES...AND PROGGED TO CONTINUE INTO THE
NORTH ATLANTIC TODAY INTO EARLY SATURDAY.  AS THIS OCCURS...REMNANT
UPSTREAM IMPULSE WILL PROGRESS THROUGH THE REMAINDER OF THE OHIO
VALLEY...ACCOMPANIED BY CONTINUING SOUTHWARD SURGE OF COLD FRONT
FROM THE LOWER OHIO VALLEY/SOUTHERN PLAINS THROUGH WESTERN AND
CENTRAL GULF COASTAL AREAS.  LOW-LEVEL COLD ADVECTION THROUGH MUCH
OF THE CENTRAL U.S. FROM THE LEE OF THE ROCKIES INTO THE WESTERN
SLOPES OF THE APPALACHIANS WILL CONTRIBUTE TO THE EVOLUTION OF A
HIGH AMPLITUDE UPPER TROUGH...AND STRENGTHENING CYCLONIC MID/UPPER
FLOW FIELDS ACROSS THE GULF AND SOUTH ATLANTIC COAST STATES.

...SOUTHEAST STATES...
MODELS SUGGEST SIGNIFICANT CYCLOGENESIS ACROSS PARTS OF THE UPPER
OHIO VALLEY AND MID ATLANTIC COASTAL AREAS WILL NOT OCCUR UNTIL
AFTER THIS FORECAST PERIOD.  THUS...PRE-FRONTAL SOUTHERLY LOW-LEVEL
FLOW WILL REMAIN GENERALLY WEAK THROUGH AT LEAST THIS EVENING FROM
EASTERN GULF COASTAL AREAS INTO THE CAROLINAS. WITH LOW-LEVEL
FOCUS/FORCING FOR VIGOROUS CONVECTIVE DEVELOPMENT UNCERTAIN AS
WELL...SEVERE THREAT SEEMS TOO MARGINAL FOR SLIGHT RISK
PROBABILITIES AT THE PRESENT TIME.  HOWEVER...WITH UPPER 60S TO 70+
SURFACE DEW POINTS ALREADY PRESENT ACROSS NORTHERN FLORIDA/GEORGIA
COASTAL AREAS...AND LIKELY TO BEGIN RETURNING NORTHWARD TODAY...
COMBINATION OF DESTABILIZING BOUNDARY LAYER AND STRENGTHENING
VERTICAL SHEAR WILL SUPPORT AT LEAST LIMITED SEVERE POTENTIAL.

SURFACE HEATING IS EXPECTED TO BE SUFFICIENT TO CONTRIBUTE TO MIXED
LAYER CAPE ON THE ORDER OF 1000 J/KG ACROSS NORTHERN FLORIDA INTO
SOUTHEASTERN GEORGIA BY LATE THIS AFTERNOON...WHEN GULF AND ATLANTIC
COAST SEA BREEZES MAY PROVIDE FORCING FOR THUNDERSTORM ACTIVITY. 
OTHERWISE...WITH APPROACH OF A WEAK SHORT WAVE TROUGH...ADDITIONAL
STORMS MAY FORM IN PRE-FRONTAL CONFLUENT ZONE ACROSS
SOUTHERN/CENTRAL GEORGIA.  ACTIVITY WILL TEND TO DEVELOP
NORTHEASTWARD TOWARD THE CAROLINAS BY THE EVENING HOURS...WHERE/
WHEN SOUTHERLY LOW-LEVEL JET WILL BEGIN TO STRENGTHEN...BUT LOSS OF
BOUNDARY LAYER HEATING IN WARM SECTOR MAY MITIGATE SEVERE THREAT.

..KERR/CROSBIE.. 10/21/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.