

969 

WWUS20 KWNS 031642

SEL9

SPC WW 031642

MIZ000-LHZ000-LMZ000-032200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 229

NWS STORM PREDICTION CENTER NORMAN OK

1245 PM EDT THU MAY 3 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN LOWER MICHIGAN

       LAKE HURON

       LAKE MICHIGAN



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 1245 PM UNTIL

600 PM EDT.



HAIL TO 1.5 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 10 MILES NORTHWEST

OF MANISTEE MICHIGAN TO 50 MILES SOUTH OF ALPENA MICHIGAN.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU9).



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.



DISCUSSION...STORMS INCREASING NORTH OF A WARM FRONT ACROSS LOWER MI

WITH A BOWING LINE SEGMENT MOVING AT ABOUT 50KT ACROSS NRN LAKE MI.

DOWNSTREAM AIRMASS IS WARMING SUFFICIENTLY TO SUPPORT SOME THREAT

FOR DAMAGING WINDS AND PERHAPS SEVERE HAIL AS THE STORMS SPREAD

ACROSS THE NRN PORTION OF LOWER MI NEXT FEW HOURS.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 25040.





...CARBIN

