

000 

WWUS20 KWNS 171558

SEL6

SPC WW 171558

IAZ000-MNZ000-WIZ000-172300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 696

NWS STORM PREDICTION CENTER NORMAN OK

1100 AM CDT THU JUL 17 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN IOWA

       SOUTHERN INTO EAST CENTRAL MINNESOTA

       WESTERN WISCONSIN



EFFECTIVE THIS THURSDAY MORNING AND EVENING FROM 1100 AM UNTIL

600 PM CDT.



HAIL TO 2 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES NORTH

NORTHWEST OF SPENCER IOWA TO 50 MILES EAST NORTHEAST OF LA CROSSE

WISCONSIN.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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.



DISCUSSION...COMPLEX SCENARIO TODAY AS LONG-LIVED MCS CONTINUES TO

SAG S-SEWD INTO STRONG INSTABILITY NOW DEVELOPING OVER IA INTO THE

NRN MS RIVER VALLEY.  ACTIVITY IS ASSOCIATED WITH MCV WHICH IS

FORECAST TO TRACK INTO WRN WI THROUGH THE AFTERNOON...WHERE

ADDITIONAL AXIS OF MODERATE TO STRONG INSTABILITY IS FORECAST TO

DEVELOP.  ISOLATED LARGE HAIL AND DAMAGING WINDS CAN BE EXPECTED

WITH THE STRONGER STORMS...WITH ADDITIONAL POTENTIAL FOR MORE

ORGANIZED BOWING MCS THIS AFTERNOON NEAR AND EAST OF THE NRN MS

RIVER.  E-W ORIENTED BAND OF STORMS NEAR THE IA/MN BORDER WILL POSE

ADDITIONAL HAZARD OF VERY HEAVY RAINFALL/FLASH FLOODING FROM

TRAINING STORMS IF OUTFLOW STALLS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 27025.





...EVANS

