

557 

WWUS20 KWNS 261233

SEL9

SPC WW 261233

FLZ000-CWZ000-262100-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 589

NWS STORM PREDICTION CENTER NORMAN OK

830 AM EDT SUN AUG 26 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHERN FLORIDA AND FLORIDA KEYS

       COASTAL WATERS



EFFECTIVE THIS SUNDAY MORNING AND AFTERNOON FROM 830 AM UNTIL 500

PM EDT.



TORNADOES...THUNDERSTORM WIND GUSTS TO 75 MPH...AND DANGEROUS

LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES SOUTH OF MARATHON

FLORIDA TO 65 MILES NORTHEAST OF FORT MEYERS FLORIDA.  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.



DISCUSSION...SUPERCELL/TORNADO POTENTIAL WILL INCREASE THROUGH AT

LEAST MID-LATE AFTERNOON AS CENTER OF ISAAC MOVES TOWARD LOWER

KEYS...STRENGTHENS FURTHER...AND LOW-LEVEL WIND FIELDS EXPAND PER

LATEST NHC GUIDANCE.  MEANWHILE INSTABILITY ALREADY IS FAVORABLE

OVER COASTAL SE FL WITH MLCAPE GREATER THAN 1500 J/KG IN 12Z MFL

RAOB.  RICHEST BOUNDARY-LAYER THETAE WILL SPREAD FARTHER WWD ACROSS

SRN FL WITH TIME...AS WILL PROGRESSIVELY MORE FAVORABLE LOW-LEVEL

HODOGRAPHS.



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

TURBULENCE AND SURFACE WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI

WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR 10040.





...EDWARDS

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