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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 184

NWS STORM PREDICTION CENTER NORMAN OK

100 PM CDT FRI APR 20 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN LOUISIANA

       SOUTHEAST TEXAS

       COASTAL WATERS



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 100 PM UNTIL 800

PM CDT.



HAIL TO 2 INCHES 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 65

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES NORTH

NORTHWEST OF BEEVILLE TEXAS TO 40 MILES EAST NORTHEAST OF FORT

POLK LOUISIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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.



DISCUSSION...STRONG COLD FRONT WILL SWEEP ACROSS THESE AREAS THROUGH

LATE THIS AFTERNOON/EARLY EVENING. WHILE MUCH OF PRE-FRONTAL AIRMASS

IS CURRENTLY CAPPED TO SURFACE-BASED CONVECTION...LATEST OBJECTIVE

DATA SUGGESTS THAT THIS CAP IS WEAKENING. FURTHER WEAKENING APPEARS

LIKELY AS FRONT SURGES INTO THE REGION AND AIDS IN LIFTING A

WARM/MOIST AIRMASS WHERE MLCAPE VALUES RANGE FROM ABOUT 500 J/KG IN

THE ERN PORTIONS OF THE WATCH...TO OVER 2000 J/KG ACROSS PARTS OF

SCNTRL TX. RESULTING TSTM DEVELOPMENT SHOULD BE INCREASINGLY

VIGOROUS THROUGH THE AFTERNOON. GIVEN STEEP LAPSE RATES AND

SUPPORTIVE LARGE SCALE ASCENT...MULTICELL STORM COVERAGE...BECOMING

MARGINALLY ORGANIZED ALONG OR IMMEDIATELY BEHIND THE FRONT SHOULD

CONTRIBUTE TO AN UPTICK IN LARGE HAIL AND SCATTERED DAMAGING WIND

EVENTS.



AVIATION...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 500. MEAN STORM

MOTION VECTOR 29025.





...CARBIN

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