

530 

WWUS20 KWNS 270055

SEL9

SPC WW 270055

IAZ000-MNZ000-270800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 419

NWS STORM PREDICTION CENTER NORMAN OK

755 PM CDT SAT JUN 26 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND NORTHERN IOWA

       SOUTHEAST MINNESOTA



EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 755 PM

UNTIL 300 AM CDT.



HAIL TO 2 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 85

STATUTE MILES EAST AND WEST OF A LINE FROM 75 MILES SOUTH

SOUTHEAST OF FORT DODGE IOWA TO 5 MILES NORTH NORTHWEST OF

MINNEAPOLIS MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 415...WW 416...WW

417...WW 418...



DISCUSSION...LINE OF INTENSE THUNDERSTORMS OVER SOUTHERN MN AND

NORTHWEST IA WILL TRACK SOUTHEASTWARD ACROSS THE WATCH AREA THIS

EVENING.  STRONG INSTABILITY AND SUFFICIENT FLOW ALOFT...COUPLED

WITH INCREASING MESOSCALE ORGANIZATION OF STORMS...SUGGEST THE

POTENTIAL FOR BOW ECHO FORMATION AND AN ASSOCIATED RISK OF DAMAGING

WINDS.  LARGE HAIL IS ALSO POSSIBLE IN THE STRONGER CELLS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

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

MOTION VECTOR 29035.





...HART

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