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537 

WWUS20 KWNS 132127

SEL6

SPC WW 132127

MIZ000-OHZ000-LEZ000-140500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 776

NWS STORM PREDICTION CENTER NORMAN OK

530 PM EDT SAT AUG 13 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST LOWER MICHIGAN

       NORTHWEST OHIO

       LAKE ERIE



EFFECTIVE THIS SATURDAY AFTERNOON AND SUNDAY MORNING FROM 530 PM

UNTIL 100 AM EDT.



HAIL TO 1 INCH 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 40

STATUTE MILES EAST AND WEST OF A LINE FROM 5 MILES NORTH

NORTHEAST OF FLINT MICHIGAN TO 55 MILES SOUTHEAST OF TOLEDO OHIO.

 FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU6).



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 775...



DISCUSSION...PREFRONTAL SQUALL LINE WITH HAIL TO 1 INCH AND WIND

GUSTS TO 50KT WILL CONTINUE TO SPREAD EAST ACROSS SOUTHERN LOWER MI

AND INTO EXTREME NWRN OH OVER THE NEXT FEW HOURS. CONVECTIVE SYSTEM

IS IN RESPONSE TO LARGE SCALE TROUGH AMPLIFICATION ACROSS THE REGION

AND...DESPITE SOME BOUNDARY LAYER STABILIZATION LIKELY LATER THIS

EVENING...IT APPEARS THAT FORCING AND AVAILABLE INSTABILITY MAY

SUSTAIN SOME SEVERE WEATHER THREAT BEYOND SUNSET.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION

VECTOR 26025.





...CARBIN

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