SWODY1
SPC AC 101246
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0646 AM CST FRI FEB 10 2012
VALID 101300Z - 111200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
EMBEDDED WITHIN BROAD MID/UPPER-LEVEL CYCLONIC FLOW OVER MUCH OF THE
ERN/CNTRL CONUS...ONE SHORTWAVE TROUGH WILL MOVE SSEWD ACROSS THE
N-CNTRL CONUS...AND ANOTHER SHORTWAVE TROUGH WILL QUICKLY MOVE EWD
FROM THE SRN PLAINS TOWARD THE E COAST. THE NRN TROUGH WILL BE
ASSOCIATED WITH THE SWD/SEWD PROGRESSION OF A POLAR FRONT ACROSS
PARTS OF THE CNTRL/ERN CONUS...WHILE THE SRN TROUGH SUPPORTS
CYCLOGENESIS INVOF THE EAST FL PENINSULA COAST AND ADJACENT WATERS
OF THE SW NORTH ATLANTIC. FARTHER W...A SHORTWAVE TROUGH OFF THE
NWRN/W-CNTRL CONUS COAST IS FORECAST TO MOVE EWD AND AID IN THE
DEAMPLIFICATION OF A DOWNSTREAM RIDGE EXTENDING FROM THE NRN GREAT
BASIN TO THE SWRN STATES.
...CNTRL/ERN FL PENINSULA...
A WEAK SFC BOUNDARY LIES NNE TO SSW FROM JUST EAST OF ST AUGUSTINE
TOWARD THE NORTH SHORE OF LAKE OKEECHOBEE AND BECOMES RATHER DIFFUSE
FARTHER SSW TOWARD THE SRN TIP OF THE PENINSULA. RELATIVELY WARM
TEMPERATURES AND RICH MOISTURE IN THE LOW LEVELS -- SFC DEWPOINTS IN
THE MIDDLE 60S TO AROUND 70 DEGREES -- TO THE EAST OF THE BOUNDARY
ARE BEING SUPPORTED...IN PART...BY HEAT/MOISTURE FLUXES ATOP THE
GULF STREAM. WITH THE ELY FLOW REGIME IN PLACE...THE BOUNDARY WILL
SLOWLY SHIFT WWD THROUGH THE DAY...WITH MLCAPE VALUES REACHING
500-1000 J/KG NEAR AND EAST OF THE BOUNDARY DURING PEAK HEATING.
INLAND TRANSPORT OF LOW-LEVEL MOISTURE MAY ALSO BE SUPPORTED BY THE
DEVELOPMENT OF AN EAST COAST SEA BREEZE CIRCULATION/BOUNDARY.
MID-LEVEL HEIGHT FALLS AND ASCENT WILL INCREASE WITH THE APPROACH OF
THE SRN SHORTWAVE TROUGH. IN RESPONSE...A WEAK SFC WAVE IS FORECAST
TO DEVELOP INVOF THE BOUNDARIES BY LATE AFTERNOON BEFORE SHIFTING
NEWD OFF THE FL COAST THIS EVENING WHILE INTENSIFYING. LOW-LEVEL
CONVERGENCE NEAR THE WAVE AND BOUNDARIES WILL SUPPORT THE
DEVELOPMENT OF ISOLATED TO SCATTERED THUNDERSTORMS BY
MID-AFTERNOON...WHICH WILL MOVE ENEWD INTO THE WEAKLY UNSTABLE AIR
MASS. WITH A VERTICALLY VEERING WIND PROFILE IN THE LOWER/MIDDLE
TROPOSPHERE AND 40-50 KT OF WSWLY 500-MB FLOW...DEEP-LAYER SHEAR
WILL BE SUFFICIENT FOR MULTICELL CLUSTERS AND POSSIBLY A COUPLE OF
WEAK SUPERCELLS. WHILE LOW-LEVEL FLOW IS EXPECTED TO BE
WEAK...WATER-LOADING PROCESSES OWING TO PW VALUES AROUND 1.5 INCHES
WILL SUPPORT STRONG -- AND POSSIBLY ONE OR TWO INSTANCES OF SVR --
WIND GUSTS WITH THE MORE ORGANIZED CONVECTION. ADDITIONALLY...
BOUNDARY INTERACTIONS AMIDST ADEQUATE LOW-LEVEL MOISTURE/BUOYANCY
MAY SERVE TO LOCALLY ENHANCE CONVECTION AND PROVIDE THE THREAT FOR A
WEAK/BRIEF TORNADO. STORMS ARE EXPECTED TO HAVE MOVED OFF THE EAST
COAST BY MID-EVENING AS THE WAVE AND BOUNDARIES ALSO MOVE OFF THE
COAST.
...ELSEWHERE...
ELEVATED INSTABILITY AND A FEW THUNDERSTORMS ARE EXPECTED TO AFFECT
THE COAST OF THE CAROLINAS AND GA THIS EVENING AND OVERNIGHT
TONIGHT. THIS WILL OCCUR AS THE PREVIOUSLY MENTIONED SFC WAVE
DEVELOPS NEWD INTO THE SWRN NORTH ATLANTIC AND INTENSIFIES...WHILE
MID-LEVEL ASCENT CROSSES PARTS OF THE SOUTHEAST AND MID-ATLANTIC
STATES. THESE STORMS ARE NOT EXPECTED TO BE SEVERE GIVEN MARGINAL
BUOYANCY AND THE PRESENCE OF A LOW-LEVEL STABLE LAYER.
A FEW THUNDERSTORMS WILL ALSO BE POSSIBLE TODAY ACROSS SERN TX AND
SWRN LA AS THE SRN SHORTWAVE TROUGH CROSSES THE AREA...AND MARGINAL
ELEVATED INSTABILITY COUPLES WITH MID-LEVEL ASCENT.
AN ISOLATED THUNDERSTORM OR TWO CANNOT BE RULED OUT THIS AFTERNOON
INTO TONIGHT ACROSS ORE...FAR SRN WA...AND FAR NRN CA AS MID-LEVEL
ASCENT ASSOCIATED WITH THE SHORTWAVE TROUGH OFF THE NWRN/W-CNTRL
CONUS COAST OVERSPREADS THE AREA. HOWEVER...THE ANTICIPATED WEAK
NATURE OF THE ASCENT AND VERY MARGINAL INSTABILITY PRECLUDE
INTRODUCTION OF A GENERAL THUNDER AREA ACROSS THE NWRN STATES ATTM.
..COHEN/MEAD.. 02/10/2012
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