Saturday, March 29, 2008

DAY3SVR: Nws Storm Prediction Center Norman Ok

ACUS03 KWNS 290735
SWODY3
SPC AC 290733

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0233 AM CDT SAT MAR 29 2008

VALID 311200Z - 011200Z

..THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
PLAINS...MID MS VALLEY AND LOWER OH VALLEY...

..OZARK PLATEAU/SRN PLAINS AND LOWER OH VALLEY...
MEDIUM RANGE MODEL FORECASTS CONTINUE TO BRING A BROAD UPPER-LEVEL
TROUGH OVER THE ROCKIES INTO THE PLAINS MONDAY AS A COLD FRONT MOVES
SEWD ACROSS THE SRN PLAINS AND MID MS VALLEY REGION. A LARGE AREA OF
CONVECTION IS LIKELY TO BE ONGOING EARLY IN THE PERIOD FROM OK NEWD
ACROSS MO INTO IL. THIS WILL AFFECT DESTABILIZATION ACROSS PARTS OF
THE WARM SECTOR MONDAY AFTERNOON. HOWEVER...SFC DEWPOINTS SHOULD BE
IN THE LOWER TO MID 60S F FROM NE TX NEWD INTO SW MO SUGGESTING
MODERATE INSTABILITY WILL LIKELY DEVELOP OVER A LARGE AREA BY MONDAY
AFTERNOON. IN ADDITION...LARGE-SCALE ASCENT WILL BE STRONG AS THE
UPPER-LEVEL TROUGH MOVES INTO THE PLAINS WHICH COMBINED WITH AN
UNCAPPED AIRMASS ACROSS MOST OF THE WARM SECTOR SHOULD PROMOTE
WIDESPREAD THUNDERSTORM DEVELOPMENT FROM THE SRN PLAINS NEWD INTO
THE LOWER OH VALLEY.

CONCERNING THE SEVERE POTENTIAL...MODEL FORECASTS EJECT A 60 TO 70
KT MID-LEVEL JET EWD ACROSS THE PLAINS DURING THE DAY AND THIS
FEATURE WILL HELP TO CREATE STRONG VERTICAL SHEAR PROFILES ACROSS
THE REGION. THE STRONG SHEAR AND AMOUNT OF LARGE-SCALE ASCENT
ASSOCIATED WITH THE UPPER-LEVEL TROUGH SUGGESTS A SQUALL-LINE WILL
DEVELOP ALONG OR JUST AHEAD OF THE COLD FRONT FROM NRN MO SWWD INTO
SE KS BY LATE AFTERNOON. SUPERCELLS AND BOW ECHOES WILL BE POSSIBLE
EMBEDDED IN THE LINE WITH MORE DISCRETE SUPERCELLS POSSIBLE FURTHER
SOUTH ACROSS ERN OK AND WRN AR WHERE STORM COVERAGE MAY BE SLIGHTLY
LESS. LOW-LEVEL SHEAR PROFILES SHOULD BE QUITE STRONG AND A TORNADO
THREAT APPEARS LIKELY TO DEVELOP ACROSS PARTS OF THE SRN PLAINS AND
OZARK PLATEAU. IN ADDITION...THE WIND DAMAGE POTENTIAL MAY BECOME
ENHANCED DURING THE EVENING DUE TO VEERING LOW-LEVEL WIND PROFILES
AS THE COLD FRONT ADVANCES SEWD. THE AMOUNT OF INSTABILITY FORECAST
ALSO SUGGESTS THE SEVERE THREAT SHOULD CONTINUE INTO THE OVERNIGHT
PERIOD AS THE SQUALL-LINE MOVES INTO THE ERN PART OF THE SLIGHT RISK
AREA.

.BROYLES.. 03/29/2008

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@PO.UIUC.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.

No comments: