

000 

WWUS20 KWNS 212343

SEL9

SPC WW 212343

IAZ000-ILZ000-MOZ000-WIZ000-220500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 439

NWS STORM PREDICTION CENTER NORMAN OK

645 PM CDT THU JUN 21 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF EASTERN IOWA

       PARTS OF NORTHWESTERN ILLINOIS

       SMALL PART OF NORTHEAST MISSOURI

       PARTS OF SOUTHWESTERN WISCONSIN



EFFECTIVE THIS THURSDAY NIGHT FROM 645 PM UNTIL MIDNIGHT CDT.



HAIL TO 2 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 65

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTH

NORTHEAST OF LONEROCK WISCONSIN TO 50 MILES SOUTHWEST OF

BURLINGTON IOWA.  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.



OTHER WATCH INFORMATION...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 434...SEVERE THUNDERSTORM WATCH

NUMBER 436. WATCH NUMBER 434 436 WILL NOT BE IN EFFECT AFTER 645

PM CDT. CONTINUE...WW 435...WW 437...WW 438...



DISCUSSION...ORGANIZED LINE OF SEVERE THUNDERSTORMS MOVING EWD

ACROSS ERN IA WILL CONTINUE DAMAGING WIND THREAT FOR SEVERAL HOURS

AS AIR MASS ACROSS WATCH IS MDTLY UNSTABLE.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 27030.





...HALES

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