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262 

WWUS20 KWNS 171752

SEL0

SPC WW 171752

IAZ000-KSZ000-MOZ000-NEZ000-180200-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 440

NWS STORM PREDICTION CENTER NORMAN OK

1255 PM CDT WED JUN 17 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHWEST IOWA

       PARTS OF NORTHEAST KANSAS

       PARTS OF NORTHWEST MISSOURI

       PARTS OF SOUTH CENTRAL AND SOUTHEAST NEBRASKA



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 1255 PM UNTIL

900 PM CDT.



TORNADOES...HAIL TO 4 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 65 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 70 MILES EAST OF SHENANDOAH

IOWA TO 50 MILES WEST SOUTHWEST OF KEARNEY NEBRASKA.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU0).



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 439...



DISCUSSION...EXTREMELY UNSTABLE AIRMASS WITH MLCAPES AOA 4000 J/KG

SPREADING NWD WITH WARM FRONT ACROSS THE WATCH. EFFECTIVE SHEAR

SUPPORTIVE OF SUPERCELLS WHICH INITIALLY WILL INCLUDE VERY LARGE

HAIL.  TORNADO THREAT WILL INCREASE DURING THE AFTERNOON AS STORMS

CONTINUE TO DEVELOP ALONG AND N OF THE WARM FRONT.



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

SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE

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

600. MEAN STORM MOTION VECTOR 26035.





...HALES

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