[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 300522
SWODY2
SPC AC 300521

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1221 AM CDT SUN OCT 30 2005

VALID 311200Z - 011200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 55 SE
PSX SAT BWD SPS 20 S MLC 10 WNW DEQ IER 50 S LCH.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 WSW FMY 35 ENE
VRB.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 NW DRT 25 WNW BGS
25 WNW CDS AVK ICT LWD 30 WSW RHI 95 NNW ANJ ...CONT... 65 E OSC LAN
MVN MKL JAN 70 SW HUM.

...THERE IS A SLGT RISK OF SVR TSTMS MONDAY/MONDAY NIGHT ACROSS
PARTS OF THE SRN PLAINS/WRN GULF COASTAL AREAS....

DE-AMPLIFICATION OF LARGE-SCALE UPPER FLOW APPEARS UNDERWAY ACROSS
THE EASTERN STATES.  AS THE TRANSITION TOWARD A MORE ZONAL REGIME
CONTINUES ACROSS THIS REGION...MODELS INDICATE UPSTREAM PATTERN
...FROM THE EASTERN PACIFIC INTO THE WESTERN AND CENTRAL U.S... WILL
BECOME MORE AMPLIFIED.

LOW AMPLITUDE TROUGH HAS ALREADY ENCOMPASSED MUCH OF THE NATION FROM
THE PACIFIC COAST INTO PARTS OF THE MISSISSIPPI VALLEY.  SEVERAL
SMALLER SCALE TROUGHS ARE EMBEDDED WITHIN BROADER CYCLONIC
REGIME...INCLUDING A COUPLE OF SOUTHERN STREAM IMPULSES NOW
PROGRESSING INTO/ACROSS THE CENTRAL PACIFIC COAST AND GREAT BASIN. 
THESE FEATURES ARE PROGGED TO CONSOLIDATE INTO AN AMPLIFYING/
DIGGING SHORT WAVE TROUGH IN THE LEE OF THE SOUTHERN ROCKIES BY
EARLY MONDAY...AS A SUBTROPICAL RIDGE BUILDS INTO CALIFORNIA AND
ADJACENT AREAS OF THE INTERMOUNTAIN WEST.

MODELS CONTINUE TO INDICATE A RATHER BROAD RANGE OF POSSIBLE
SOLUTIONS CONCERNING THE SUBSEQUENT EVOLUTION OF THIS SOUTHERN
STREAM TROUGH...AND ITS INTERACTION WITH THE STRONGER NORTHERN
BRANCH OF WESTERLIES...ACROSS THE NORTHERN TIER STATES. 
HOWEVER...GIVEN CURRENT LACK OF COLDER LOW-LEVEL ADVECTION IN THE
LEE OF THE ROCKIES...MORE PROGRESSIVE SCENARIO SEEMS MOST LIKELY
THROUGH AT LEAST THE REMAINDER OF THIS FORECAST PERIOD.  LATEST NAM
RUN IS NOW  IN CLOSER AGREEMENT WITH GFS...INDICATING SHORT WAVE
WILL DIG ACROSS MUCH OF TEXAS BY LATE MONDAY NIGHT...BEFORE
BEGINNING TO EVOLVE INTO A CLOSED LOW OVER CENTRAL GULF COASTAL
AREAS.

...SOUTHERN PLAINS INTO CENTRAL/WESTERN GULF COASTAL AREAS...
LOW-LEVEL WIND FIELDS/FRONTAL WAVE DEVELOPMENT ASSOCIATED WITH
DIGGING SHORT WAVE TROUGH LIKELY WILL REMAIN FAIRLY WEAK. 
HOWEVER...PERSISTENT SURFACE RIDGE ACROSS GULF COASTAL AREAS IS
FINALLY FORECAST TO WEAKEN EARLY MONDAY...AND MODIFICATION OF
BOUNDARY LAYER OVER THE WESTERN GULF OF MEXICO IS EXPECTED TO YIELD
WEAK TO MODERATE INSTABILITY AHEAD OF FRONT ACROSS PARTS OF
CENTRAL/EASTERN TEXAS. WITH AT LEAST LOWER 60S SURFACE DEW
POINTS...LAPSE RATES ARE EXPECTED TO BE STEEP ENOUGH FOR CAPE IN
EXCESS OF 1000 J/KG.

FORCING IN EXIT REGION OF CYCLONIC MID-LEVEL JET MAY SUPPORT
CONVECTIVE DEVELOPMENT IN WARM SECTOR ACROSS NORTH CENTRAL TEXAS AS
EARLY AS MIDDAY MONDAY.  EVOLUTION INTO PRE-FRONTAL SQUALL LINE THEN
APPEARS POSSIBLE...SOUTHEASTWARD ACROSS CENTRAL/EASTERN TEXAS MONDAY
AFTERNOON AND EVENING. DESPITE WEAKNESS OF LOW-LEVEL FLOW ...DEEP
LAYER SHEAR SHOULD BE SUFFICIENT FOR MID-LEVEL UPDRAFT
ROTATION...ENHANCING RISK OF AT LEAST MARGINAL SEVERE HAIL/WINDS IN
STRONGER STORMS.  SEVERE THREAT COULD PERSIST WITH CONVECTION INTO
UPPER TEXAS COASTAL AREAS LATE MONDAY EVENING BEFORE DIMINISHING.

...MID MISSISSIPPI VALLEY INTO UPPER GREAT LAKES...
FORCING/DESTABILIZATION ASSOCIATED WITH NORTHERN BRANCH SHORT WAVE
MAY BECOME SUPPORTIVE OF CONVECTIVE DEVELOPMENT MONDAY.  ANY
THUNDERSTORM ACTIVITY...HOWEVER...IS EXPECTED TO BE SPARSE IN
COVERAGE.

...FLORIDA PENINSULA...
SURFACE FRONT IS EXPECTED TO REMAIN SOUTH OF THE PENINSULA/KEYS INTO
THE SOUTHERN GULF OF MEXICO MONDAY...BUT MODIFICATION OF BOUNDARY
LAYER IN EASTERLY FLOW TO THE NORTH COULD BECOME SUFFICIENT FOR
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS.

..KERR.. 10/30/2005

...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.