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000 

WWUS20 KWNS 310625

SEL8

SPC WW 310625

SDZ000-311200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 778

NWS STORM PREDICTION CENTER NORMAN OK

125 AM CDT THU JUL 31 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTH CENTRAL INTO NORTHEAST SOUTH DAKOTA



EFFECTIVE THIS THURSDAY MORNING FROM 125 AM UNTIL 700 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 85

STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES NORTHEAST OF

MOBRIDGE SOUTH DAKOTA TO 60 MILES WEST SOUTHWEST OF WATERTOWN

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

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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 777...



DISCUSSION...SMALL BOWING MCS/HP-SUPERCELL OVER S-CENTRAL ND EARLY

THIS MORNING IS EXPECTED TO CONTINUE SEWD ALONG PERIPHERY OF STRONG

CAPPING INVOF SURFACE FRONT OVERNIGHT INTO NRN/NERN SD.  VERY STRONG

WINDS AND ISOLATED LARGE HAIL CAN BE EXPECTED WITH THIS ACTIVITY.

AS LLJ INCREASES AND BECOMES MORE SWLY TONIGHT...ELEVATED STORMS

WITH THREAT OF LARGE HAIL MAY ALSO PERSIST ATOP SURFACE COLD POOL IN

WAKE OF LEADING STORMS THROUGH DAY BREAK.



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 500. MEAN STORM

MOTION VECTOR 31035.





...EVANS

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