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487 

WWUS20 KWNS 052203

SEL2

SPC WW 052203

LAZ000-TXZ000-060300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 552

NWS STORM PREDICTION CENTER NORMAN OK

500 PM CDT SUN JUL 5 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWESTERN LOUISIANA

       EAST CENTRAL TEXAS



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 500 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES SOUTH OF

TYLER TEXAS TO 45 MILES SOUTH SOUTHEAST OF SHREVEPORT LOUISIANA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 550...WW 551...



DISCUSSION...INTENSE STORMS HAD RECENTLY DEVELOPED ALONG

INTERSECTION OF TWO OUTFLOW BOUNDARIES...ABOUT 35 SOUTHWEST OF TYR.

THESE STORMS ARE LIKELY TO REMAIN STRONG INTO THE EVENING HOURS AS

THEY SHIFT ESEWD ALONG OUTFLOW BOUNDARY THAT EXTENDS SEWD FROM THE

STORMS TO NORTH OF POE. STRONG INSTABILITY...HIGH PRECIPITABLE WATER

VALUES AND TEMPERATURES NEAR 100 DEGREES...ON THE SOUTH SIDE OF THE

BOUNDARY...ARE LIKELY TO SUPPORT A WIND THREAT WITH THESE STORMS.

ALSO...OTHER SEVERE STORMS ARE POSSIBLE ACROSS PORTIONS OF ERN

TX/NWRN LA IN VERY MOIST AIR MASS.



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 600. MEAN STORM

MOTION VECTOR 29020.





...IMY

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