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177 

WWUS20 KWNS 302156

SEL0

SPC WW 302156

NDZ000-SDZ000-010400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 440

NWS STORM PREDICTION CENTER NORMAN OK

400 PM MDT SAT JUN 30 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTH CENTRAL NORTH DAKOTA

       CENTRAL AND WESTERN SOUTH DAKOTA



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 400 PM UNTIL

1000 PM MDT.



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 45

STATUTE MILES EAST AND WEST OF A LINE FROM 105 MILES NORTH

NORTHEAST OF MOBRIDGE SOUTH DAKOTA TO 95 MILES SOUTHWEST OF

PHILIP SOUTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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...SCATTERED THUNDERSTORMS ARE INTENSIFYING ALONG A

BOUNDARY EXTENDING FROM THE BIS AREA SOUTHWESTWARD INTO THE BLACK

HILLS.  HIGH CAPE VALUES AND SUFFICIENT EFFECTIVE SHEAR WILL PROMOTE

THE RISK OF SUPERCELLS CAPABLE OF HAIL AND DAMAGING WINDS THROUGH

THE EVENING.  UNCERTAINTY REMAINS HOW MANY SEVERE STORMS WILL

MATERIALIZE...BUT THREAT APPEARS SUFFICIENT TO WARRANT A WATCH.



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 500. MEAN STORM

MOTION VECTOR 30020.





...HART

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