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805 

WWUS20 KWNS 242312

SEL6

SPC WW 242312

MNZ000-SDZ000-250600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 506

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT WED JUN 24 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF SOUTHWESTERN MINNESOTA

       MUCH OF CENTRAL AND EASTERN SOUTH DAKOTA



EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 615 PM

UNTIL 100 AM 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 45 MILES WEST

SOUTHWEST OF MOBRIDGE SOUTH DAKOTA TO 40 MILES NORTH OF

WORTHINGTON MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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...CONTINUE...WW 505...



DISCUSSION...THUNDERSTORMS EXPECTED TO INCREASE IN NUMBER AND

INTENSITY VICINITY AND N OF E/W SURFACE BOUNDARY AS AIR MASS HAS

BECOME MDTLY UNSTABLE AND WEAKLY CAPPED.  SUFFICIENT SHEAR ALONG

WITH INSTABILITY FOR DEVELOPMENT OF SUPERCELLS WHICH WOULD ENHANCE

BOTH LARGE HAIL AND WIND THREAT DURING THE EVENING.



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 550. MEAN STORM

MOTION VECTOR 28030.





...HALES

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