

000 

WWUS20 KWNS 270435

SEL7

SPC WW 270435

SDZ000-271100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 757

NWS STORM PREDICTION CENTER NORMAN OK

1135 PM CDT SAT JUL 26 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST SOUTH DAKOTA



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 1135 PM

UNTIL 600 AM CDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHEAST OF

HURON SOUTH DAKOTA TO 55 MILES WEST OF YANKTON SOUTH DAKOTA.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 755...WW 756...



DISCUSSION...NOCTURNAL MCS EXPECTED TO REMAIN SEVERE AS IT TRACKS

ESEWD WITHIN WELL DEFINED INSTABILITY AXIS ACROSS CNTRL AND SERN SD

LATE TONIGHT. WIND GUSTS OF 50-70KT HAVE ACCOMPANIED THIS

FAST-MOVING LINEAR MCS AND THIS THREAT SHOULD DEVELOP ACROSS

PORTIONS OF SERN SD OVER THE NEXT 4-5 HOURS.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 28030.





...CARBIN

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