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WWUS20 KWNS 101929

SEL0

SPC WW 101929

INZ000-OHZ000-LMZ000-110000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 270

NWS STORM PREDICTION CENTER NORMAN OK

330 PM EDT TUE MAY 10 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN INDIANA

       NORTHWEST OHIO

       LAKE MICHIGAN



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 330 PM UNTIL

800 PM EDT.



HAIL TO 3 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 35

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

OF VALPARAISO INDIANA TO 60 MILES EAST SOUTHEAST OF FORT WAYNE

INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 268...WW 269...



DISCUSSION...WIDELY SCATTERED STORMS MAY CONTINUE DEVELOPING IN

VICINITY OF NW-SE ORIENTED BOUNDARY. THE ATMOSPHERE HAS BECOME VERY

UNSTABLE WITH 3000-4000 J/KG MLCAPE AND 35-40 KT EFFECTIVE SHEAR

SUPPORTIVE OF SUPERCELLS. VERY LARGE HAIL AND DAMAGING WIND WILL BE

THE MAIN THREATS THROUGH EARLY EVENING.



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

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 29035.





...DIAL

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