SPC Severe Thunderstorm Watch 572

WW 572 SEVERE TSTM LA TX CW 102130Z - 110500Z
URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 572 NWS STORM PREDICTION CENTER NORMAN OK 430 PM CDT FRI AUG 10 2012 THE NWS STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF SOUTHWEST LOUISIANA SOUTH CENTRAL AND SOUTHEAST TEXAS COASTAL WATERS EFFECTIVE THIS FRIDAY AFTERNOON FROM 430 PM UNTIL MIDNIGHT CDT. HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE MILES EITHER SIDE OF A LINE FROM 15 MILES WEST SOUTHWEST OF SAN ANTONIO TEXAS TO 60 MILES EAST NORTHEAST OF LAKE CHARLES LOUISIANA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2). REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES. OTHER WATCH INFORMATION...CONTINUE...WW 571... DISCUSSION...TSTMS EXPECTED TO CONTINUE FORMING ALONG W-E FRONT DRIFTING SLOWLY S ACROSS PARTS OF TX AND LA...WHERE VERY STEEP LOW LVL LAPSE RATES/DEEPLY MIXED BOUNDARY LAYER IN CONJUNCTION WITH HIGH PW MAY FOSTER WET MICROBURSTS. UPR LVL WINDS ARE WEAKER ACROSS REGION RELATIVE TO YESTERDAY...BUT STILL SUFFICIENT FOR POSSIBLE UPSCALE GROWTH INTO A SMALL SWD-MOVING CLUSTER OR TWO. SUSTAINED ACTIVITY ALSO MAY BE FOSTERED BY PRESENCE OF A MORE MOIST MID LVL ENVIRONMENT RELATIVE TO YESTERDAY. THE 20Z CONVECTIVE OUTLOOK WILL BE AMENDED TO INCLUDE 15% WIND PROBABILITIES IN THE WW REGION. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR 34020. ...CORFIDI Read more

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