

427 

WWUS20 KWNS 270313

SEL4

SPC WW 270313

MNZ000-NEZ000-SDZ000-270900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 524

NWS STORM PREDICTION CENTER NORMAN OK

1015 PM CDT FRI JUN 26 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       PARTS OF SOUTHWEST MINNESOTA

       SMALL PART OF NORTHEAST NEBRASKA

       PARTS OF EASTERN SOUTH DAKOTA



EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 1015 PM

UNTIL 400 AM CDT.



HAIL TO 1.5 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 55

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

SOUTHWEST OF YANKTON SOUTH DAKOTA TO 5 MILES NORTH NORTHWEST OF

ORTONVILLE MINNESOTA.  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...THIS SEVERE THUNDERSTORM WATCH REPLACES

TORNADO WATCH NUMBER 521. WATCH NUMBER 521 WILL NOT BE IN EFFECT

AFTER 1015 PM CDT. CONTINUE...WW 520...WW 522...WW 523...



DISCUSSION...MATURE FORWARD PROPAGATING SQUALL LINE WITH A WELL

DEVELOPED COLD POOL EXPECTED TO CONTINUE RAPIDLY NE THRU A MOIST

UNSTABLE AIRMASS.  WIND DAMAGE WILL BE THE PRIMARY THREAT ASSOCIATED

WITH THE LINE.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 23040.





...HALES

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