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000 

WWUS20 KWNS 290314

SEL0

SPC WW 290314

MNZ000-SDZ000-290900-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 770

NWS STORM PREDICTION CENTER NORMAN OK

1010 PM CDT MON JUL 28 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       WESTERN MINNESOTA

       NORTHEASTERN SOUTH DAKOTA



EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 1010 PM

UNTIL 400 AM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 60 MILES WEST SOUTHWEST OF

ABERDEEN SOUTH DAKOTA TO 40 MILES EAST NORTHEAST OF WATERTOWN

SOUTH DAKOTA.  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 767...WW 768...WW 769...



DISCUSSION...STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE

OF LOW LEVEL WARM ADVECTION AND WITHIN AREA OF STRONG INSTABILITY

OVER NERN SD NEXT SEVERAL HOURS. STRONG INSTABILITY WITH MLCAPE TO

4000 J/KG AND BULK SHEAR AROUND 45 KT WILL SUPPORT ORGANIZED STORMS

INCLUDING SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WIND

POSSIBLE. THE 0-1 KM HODOGRAPHS SIZE WILL INCREASE AS THE LOW LEVEL

JET STRENGTHENS WITH A WINDOW OF OPPORTUNITY FOR ISOLATED TORNADOES

BEFORE THE BOUNDARY LAYER DECOUPLES.



AVIATION...TORNADOES AND 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

600. MEAN STORM MOTION VECTOR 32025.





...DIAL/HART

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