Tuesday, March 20, 2012

Tornado Watch for WESTERN LOUISIANA, EXTREME EAST CENTRAL AND SOUTHEAST TEXAS and COASTAL WATERS


945 AM CDT TUE MAR 20 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

WESTERN LOUISIANA

EXTREME EAST CENTRAL AND SOUTHEAST TEXAS
COASTAL WATERS

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 945 AM UNTIL

500 PM CDT.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS

TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 40 STATUTE

MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH NORTHEAST OF
SHREVEPORT LOUISIANA TO 45 MILES SOUTH SOUTHEAST OF PORT ARTHUR
TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.

DISCUSSION...N-S LINE OF THUNDERSTORMS WILL CONTINUE TO DRIFT EWD

FROM E TX INTO WRN LA IN ADVANCE OF A CLOSED LOW NEAR THE NM/TX
BORDER. AN INFLUX OF BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 60S
WILL SUPPORT MODERATE INSTABILITY IN ADVANCE OF THE LINE...DESPITE
CLOUDS THAT WILL SLOW SURFACE HEATING SOMEWHAT.
ADDITIONALLY...LOW-LEVEL SLY SHEAR IS SUFFICIENT FOR CIRCULATIONS IN
THE LINE AND AN ATTENDANT RISK FOR A COUPLE OF TORNADOES AND
ISOLATED DAMAGING GUSTS THROUGH THE AFTERNOON.

AVIATION...TORNADOES AND 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 500.
MEAN STORM MOTION VECTOR 21045. Source