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000 

WWUS20 KWNS 082143

SEL1

SPC WW 082143

IAZ000-ILZ000-WIZ000-090400-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 491

NWS STORM PREDICTION CENTER NORMAN OK

445 PM CDT SUN JUN 8 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       MUCH OF EASTERN IOWA

       PARTS OF NORTHWEST ILLINOIS

       SMALL PART OF SOUTHWEST WISCONSIN



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 445 PM UNTIL

1100 PM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE

MILES EAST AND WEST OF A LINE FROM 40 MILES SOUTHEAST OF OTTUMWA

IOWA TO 40 MILES NORTHEAST OF DUBUQUE IOWA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU1).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 486...WW 487...WW

488...WW 489...WW 490...



DISCUSSION...SEVERE THUNDERSTORMS DEVELOPING ACROSS CENTRAL/NRN IA

WILL BE MOVING ENEWD INTO A FAVORABLE SHEAR AND INSTABILITY

ENVIRONMENT FOR SUPERCELLS. WITH E/W BOUNDARY SHIFTING NWD THRU ERN

IA/NWRN IL...POTENTIAL FOR TORNADOES WILL BE ENHANCED VICINITY OF

THE BOUNDARY.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

600. MEAN STORM MOTION VECTOR 24040.





...HALES

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