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919 

WWUS20 KWNS 120039

SEL4

SPC WW 120039

TXZ000-CWZ000-120700-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 274

NWS STORM PREDICTION CENTER NORMAN OK

740 PM CDT FRI MAY 11 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHEAST TEXAS

       COASTAL WATERS



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 740 PM

UNTIL 200 AM CDT.



TORNADOES...HAIL TO 1.5 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 60 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 20 MILES WEST OF HOUSTON

TEXAS TO 30 MILES NORTHEAST OF PORT ARTHUR TEXAS.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU4).



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...DISCRETE STORMS ARE EXPECTED TO PERSIST AND MAY

INCREASE IN COVERAGE AND INTENSITY FROM HOUSTON AREA EAST TO THE

SABINE PASS THROUGH THE LATE EVENING. RICH LOW LEVEL MOISTURE BEING

LIFTED ACROSS A WEAK WARM FRONT ACROSS THESE AREAS APPEARS TO BE

CONTRIBUTING TO TSTM DEVELOPMENT AND MAY BE FURTHER AIDED AS LARGE

SCALE UPPER TROUGH APPROACHES THE REGION TONIGHT. DEEP-LAYER

VERTICAL SHEAR IS SUFFICIENT TO MAINTAIN ORGANIZED UPDRAFTS WHILE

LOW LEVEL STORM RELATIVE SHEAR NEAR AND ALONG THE WARM FRONT WILL

OCCASIONALLY FAVOR LOW LEVEL UPDRAFT ROTATION AND A CHANCE FOR A

TORNADO OR TWO. THIS TORNADO POTENTIAL WILL ALSO BE SUPPORTED BY

HIGH BOUNDARY LAYER RH AND LOW LFC LEVELS AOB 1KM.



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

SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE

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

450. MEAN STORM MOTION VECTOR 27025.





...CARBIN

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