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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 377

NWS STORM PREDICTION CENTER NORMAN OK

1210 AM EDT TUE JUN 22 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHEASTERN INDIANA

       SOUTHERN LOWER MI MICHIGAN

       LAKE MICHIGAN



EFFECTIVE THIS TUESDAY MORNING FROM 1210 AM UNTIL 700 AM EDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH

NORTHWEST OF LANSING MICHIGAN TO 35 MILES SOUTH SOUTHEAST OF

KALAMAZOO MICHIGAN.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 371...WW 374...WW

375...WW 376...



DISCUSSION...A LINE OF STORMS...CURRENTLY MOVING EWD AT 35-40 KT

ACROSS SRN LAKE MI...ARE BEING SUPPORTED BY A MID LEVEL UPPER TROUGH

MOVING THROUGH THE GREAT LAKES AREA. THIS FEATURE SHOULD MAINTAIN

STORMS EWD ACROSS SRN LOWER MI. DESPITE SOME WEAK NIGHTTIME

COOLING...THE COMBINATION OF THE RAPID THUNDERSTORM LINE MOTION AND

STRENGTHENING WLY WINDS ABOVE THE BOUNDARY LAYER INDICATE WIND

DAMAGE IS LIKELY.



AVIATION...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 500. MEAN STORM

MOTION VECTOR 27035.





...IMY

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