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000 

WWUS20 KWNS 112208

SEL4

SPC WW 112208

IAZ000-MNZ000-NEZ000-SDZ000-120400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 684

NWS STORM PREDICTION CENTER NORMAN OK

510 PM CDT FRI JUL 11 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF NORTHWEST IOWA

       PARTS OF SOUTHERN MINNESOTA

       PARTS OF NORTHEAST NEBRASKA

       SMALL PART OF SOUTHEAST SOUTH DAKOTA



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 510 PM UNTIL

1100 PM CDT.



HAIL TO 3 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 70

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTHWEST OF

MANKATO MINNESOTA TO 15 MILES SOUTH SOUTHWEST OF COLUMBUS

NEBRASKA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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 683...



DISCUSSION...THUNDERSTORMS WILL INCREASE RAPIDLY IN NUMBER AND

INTENSITY ALONG THE STRONG COLD FRONT NOW MOVING EWD INTO SWRN MN

INTO NERN NE.  WITH MLCAPES TO 3500 J/KG AND 40KT OF

SHEAR...SUPERCELLS WILL BE POSSIBLE ENHANCING THE DAMAGING WIND AND

LARGE HAIL THREAT AS STORMS SPREAD EWD ACROSS THE WATCH.



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

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM

MOTION VECTOR 25025.





...HALES

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