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WWUS20 KWNS 311956

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SPC WW 311956

LAZ000-TXZ000-CWZ000-010300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 74

NWS STORM PREDICTION CENTER NORMAN OK

245 PM CDT SUN MAR 31 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       COASTAL SOUTHWEST LOUISIANA

       UPPER AND NORTHERN MIDDLE TEXAS GULF COASTAL PLAIN

       COASTAL WATERS



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 245 PM UNTIL

1000 PM CDT.



HAIL TO 1.5 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 45

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES EAST

SOUTHEAST OF LAFAYETTE LOUISIANA TO 60 MILES WEST NORTHWEST OF

ANGLETON TEXAS.  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.



OTHER WATCH INFORMATION...CONTINUE...WW 72...WW 73...



DISCUSSION...TSTMS NOW FORMING ALONG W-E FRONT SAGGING SLOWLY S

ACROSS E TX /NEAR BRYAN-COLLEGE STATION/ EXPECTED TO INCREASE IN

COVERAGE/STRENGTH DURING THE NEXT FEW HOURS AS SFC HEATING CONTINUES

S OF BOUNDARY AND AS ASCENT INCREASES WITH CONTINUED EWD MOTION OF

SW TX UPR IMPULSE. STEEP MID LVL LAPSE RATES...FAIRLY RICH LOW-LVL

MOISTURE...AND LARGELY UNIDIRECTIONAL CLOUD-LAYER FLOW ALSO SUGGEST

POTENTIAL FOR HAIL AND POSSIBLY LOCALLY DMGG WIND. WHILE INDIVIDUAL

STORMS SHOULD MOVE MAINLY E OR ESEWD...CONSOLIDATION OF STORM COLD

POOLS MAY SHIFT PROPAGATIONAL COMPONENT OF OVERALL STORM CLUSTER/MCS

MOTION A BIT FARTHER TO THE S. THIS MOTION WOULD CAUSE STORMS TO

IMPACT AREAS S OF EXISTING WWS 72 AND 73 ALONG THE UPR AND NRN

MIDDLE TX GULF CSTL PLN AND SW LA LATER THIS AFTN THROUGH EARLY

TNGT.



AVIATION...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 500. MEAN STORM

MOTION VECTOR 30035.





...CORFIDI

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