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WWUS20 KWNS 262059

SEL1

SPC WW 262059

LAZ000-TXZ000-CWZ000-270400-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 71

NWS STORM PREDICTION CENTER NORMAN OK

355 PM CDT THU MAR 26 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHERN AND SOUTHWEST LOUISIANA

       EAST CENTRAL AND SOUTHEAST TEXAS

       COASTAL WATERS



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 355 PM UNTIL

1100 PM CDT.



TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND

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

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 90 STATUTE

MILES EITHER SIDE OF A LINE FROM 45 MILES NORTHWEST OF PORT

ARTHUR TEXAS TO 40 MILES SOUTH SOUTHEAST OF ALEXANDRIA LOUISIANA.

 FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).



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.



OTHER WATCH INFORMATION...CONTINUE...WW 70...



DISCUSSION...THUNDERSTORM ARE SLOWLY INCREASING IN COVERAGE AND

INTENSITY OVER PARTS OF SERN TX...AND ACTIVITY IS EXPECTED TO SPREAD

EWD/NEWD THIS EVENING IN LEFT EXIT REGION OF STRONG UPPER LEVEL JET.

 AIR MASS HAS RECOVERED IN THE WAKE OF EARLIER OUTFLOW

BOUNDARY...WITH SURFACE DEW POINTS IN UPPER 60S AND TEMPERATURES

75-80F.  THIS IS CONTRIBUTING TO UNSTABLE ENVIRONMENT WITH MLCAPE OF

2000-2500 J/KG.  STRONG DEEP LAYER SHEAR OF 45-55 KT WILL SUPPORT

SUPERCELL DEVELOPMENT WITH POTENTIAL FOR LARGE HAIL AND DAMAGING

WIND GUSTS.  IN ADDITION...SUFFICIENT LOW LEVEL SHEAR AND HELICITY

ARE EVIDENT IN LCH 18Z RAOB AND LATEST LCH VWP SUGGESTING POTENTIAL

FOR A FEW TORNADOES.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

550. MEAN STORM MOTION VECTOR 24030.





...WEISS

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