

000 

WWUS20 KWNS 170228

SEL9

SPC WW 170228

LAZ000-TXZ000-CWZ000-170900-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 59

NWS STORM PREDICTION CENTER NORMAN OK

825 PM CST SAT FEB 16 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHWESTERN LOUISIANA

       SOUTHEAST TEXAS

       COASTAL WATERS



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 825 PM

UNTIL 300 AM CST.



TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE

MILES EITHER SIDE OF A LINE FROM 35 MILES SOUTH OF ANGLETON TEXAS

TO 25 MILES EAST OF FORT POLK LOUISIANA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU9).



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...THIS TORNADO WATCH REPLACES TORNADO

WATCH NUMBER 58. WATCH NUMBER 58 WILL NOT BE IN EFFECT AFTER 825

PM CST.



DISCUSSION...BAND OF TSTMS IS FCST TO MOVE EWD ACROSS REGION IN

ENVIRONMENT OF MARGINAL BUOYANCY...BUT VERY STRONG MAGNITUDES OF LOW

LEVEL SRH AND DEEP-LAYER SHEAR.  ALTHOUGH PRIMARY CONVECTIVE MODE

SHOULD REMAIN LINEAR...EMBEDDED BOW/LEWP CIRCULATIONS MAY POSE

TORNADO POTENTIAL...AND SOME THREAT REMAINS FOR SUPERCELLS TO

DEVELOP EITHER WITHIN MAIN LINE OR JUST TO ITS E.  DAMAGING WIND

ALSO IS A DISTINCT THREAT WITH THIS SYSTEM...ESPECIALLY AS PARENT

UPPER TROUGH OVER TX PIVOTS NEWD AND ASSOCIATED/ENHANCED GRADIENT

WINDS ALOFT OVERSPREAD WW AREA.



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

SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

450. MEAN STORM MOTION VECTOR 23035.





...EDWARDS/HART

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