SWODY2
SPC AC 140700
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CST FRI NOV 14 2008
VALID 151200Z - 161200Z
...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CAROLINAS TO
MID-ATLANTIC REGION...
...SYNOPSIS...
HIGHLY AMPLIFIED UPPER AIR PATTERN FCST THIS PERIOD...RELATED TO
STRENGTHENING AND EWD/SEWD NET MOTION OF SYNOPTIC-SCALE TROUGHING
NOW EVIDENT OVER N-CENTRAL CONUS AND CENTRAL CANADA. BY
15/12Z...CYCLONIC FLOW AROUND THIS TROUGH WILL EXTEND FROM N-CENTRAL
HIGH PLAINS ACROSS LOWER MS VALLEY TO MID/UPPER OH
VALLEY...INCLUDING 110-140 KT 250 MB JET. REGIME ALOFT THEN WILL
SHIFT EWD THROUGH PERIOD...WITH 140-150 KT UPPER JET DEVELOPING IN
FRONT OF TROUGH...OVER SRN/CENTRAL APPALACHIANS...BY 16/00Z. TROUGH
IS FCST TO MOVE EWD TO SERN ONT...MD...AND CENTRAL/SRN CAROLINAS.
AT SFC...COLD FRONT -- NOW ANALYZED FROM ERN LS SWWD ACROSS NRN
MO...NERN OK...WRN TX PANHANDLE -- IS FCST TO SURGE SEWD INTO WRN
GULF OF MEXICO DAY-1 AND EWD ACROSS MS VALLEY. DURING DAYLIGHT
HOURS..EXPECT COLD FRONT TO MOVE FROM CENTRAL/SRN APPALACHIANS EWD
TO MID-ATLANTIC COASTAL PLAIN...ACROSS MOST OF CAROLINAS...AND
OFFSHORE GA.
...CAROLINAS TO MID-ATLANTIC REGION...
SCATTERED TSTMS ARE EXPECTED TO DEVELOP -- PRIMARILY IN LINEAR MODES
-- ALONG/AHEAD OF SFC COLD FRONT ACROSS THIS REGION...BEGINNING
EARLY IN PERIOD AND CONTINUING THROUGHOUT MORNING/AFTERNOON PRIOR TO
FROPA. MAIN THREAT WILL BE DAMAGING WIND...WITH FCST LOW-LEVEL
SHEAR PROFILES INDICATING POTENTIAL FOR EITHER SUPERCELLULAR OR QLCS
RELATED TORNADOES IN A FEW LOCALES AS WELL. SVR PROBABILITIES
THEREFORE ARE BEING UPGRADED TO CATEGORICAL CRITERIA. RELATIVELY
DENSE CONCENTRATION OF CONVECTIVE WIND EVENTS...IN PARTICULAR...IS
POSSIBLE WITHIN BROADER AREA OF CATEGORICAL SLGT RISK NOW
DRAWN...AND UPGRADE TO PROBABILITIES WITHIN THIS AREA MAY BE NEEDED
IN FUTURE OUTLOOKS ONCE MESOSCALE UNCERTAINTIES ARE BETTER RESOLVED.
PREFRONTAL AIR MASS IS FCST TO DESTABILIZE FAVORABLY THROUGHOUT
DAYLIGHT HOURS...OFFSETTING WEAK LAPSE RATES ENOUGH TO REMOVE CINH
AND TO YIELD DEEPLY BUT NARROWLY BUOYANT THERMODYNAMIC
PROFILES...WITH MLCAPES 500-1000 J/KG IN MOST AREAS. VERY STG
MID-UPPER WINDS WILL AID DEEP-LAYER SHEAR...WITH FCST SOUNDINGS
SUGGESTING 55-70 KT EFFECTIVE SHEAR MAGNITUDES. 50-60 KT LLJ ALSO
WILL ENHANCE LOW LEVEL HODOGRAPHS...YIELDING FAVORABLE LOW LEVEL
SHEAR PROFILES FOR ORGANIZED BOW ECHOES...AS WELL AS FOR ANY
RELATIVELY DISCRETE STORMS TO ROTATE. ALTHOUGH VERTICAL SHEAR WILL
REMAIN FAVORABLE FARTHER N...SVR POTENTIAL WILL BECOME MORE
CONDITIONAL WITH NWD EXTENT FROM CHESAPEAKE BAY REGION UP DE RIVER
VALLEY...DUE TO MORE UNCERTAINTY ABOUT SUFFICIENCY OF DIURNAL
DESTABILIZATION.
SVR POTENTIAL ALSO WILL BE LOWER AND MORE CONDITIONAL SWD TOWARD NRN
FL. CONVERGENCE SHOULD BE WEAKER WITH SWWD EXTENT TOWARD GULF
COAST...WITH PREFRONTAL WINDS CONTAINING PROGRESSIVELY LARGER WLY
COMPONENT.
..EDWARDS.. 11/14/2008
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment