

000 

WWUS20 KWNS 142022

SEL1

SPC WW 142022

MIZ000-MNZ000-WIZ000-LSZ000-150300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 271

NWS STORM PREDICTION CENTER NORMAN OK

325 PM CDT MON MAY 14 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN U.P. OF MICHIGAN

       NORTHEASTERN MINNESOTA

       FAR NORTHERN WISCONSIN

       LAKE SUPERIOR



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 325 PM UNTIL

1000 PM CDT.



HAIL TO 2.5 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 70

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES SOUTHWEST

OF DULUTH MINNESOTA TO 10 MILES NORTH NORTHEAST OF MARQUETTE

MICHIGAN.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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...SEVERE THUNDERSTORMS ARE EXPECTED TO CONTINUE

DEVELOPING AND SPREAD FROM WEST TO EAST ACROSS WW THIS EVENING AHEAD

OF APPROACHING MID/UPPER LEVEL TROUGH.  AIR MASS IS ALREADY

MODERATELY UNSTABLE WITH SUFFICIENT SHEAR FOR SUPERCELLS AND

EVENTUAL EVOLUTION INTO SMALL LINES/BOW ECHOES.  PRIMARY SEVERE

THREATS WILL BE FROM LARGE HAIL...SOME OF WHICH COULD EXCEED GOLF

BALL SIZE...AND DAMAGING WINDS.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 26035.





...EVANS

