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339 

WWUS20 KWNS 180850

SEL0

SPC WW 180850

IAZ000-MNZ000-WIZ000-181500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 320

NWS STORM PREDICTION CENTER NORMAN OK

345 AM CDT WED JUN 18 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTH CENTRAL AND NORTHEAST IOWA

  SOUTHEAST MINNESOTA

  SOUTHWEST WISCONSIN



* EFFECTIVE THIS WEDNESDAY MORNING FROM 345 AM UNTIL 1000 AM CDT.



* PRIMARY THREATS INCLUDE...

  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF LA

CROSSE WISCONSIN TO 45 MILES WEST SOUTHWEST OF WATERLOO IOWA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU0).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 318...WW 319...



DISCUSSION...LOOSELY-ORGANIZED N CNTRL IA MCS...WITH EMBEDDED

SUSTAINED STORMS...EXPECTED TO MOVE GENERALLY EWD THROUGH LATER THIS

MORNING. DEVELOPMENT WILL BE FOSTERED BY MOIST...40+ KT WSWLY LLJ.

ALTHOUGH MID/UPR LVL WINDS DO NOT APPEAR FAVORABLE FOR A

LONG-LIVED/INTENSE MCS DRIVEN BY COLD POOL DYNAMICS...COMBINATION OF

EXISTING BUOYANCY...RICH MOISTURE /PW AROUND 1.75 INCHES/...AND

MODERATE WLY FLOW ALOFT SUGGEST POTENTIAL FOR AT LEAST SPORADIC DMGG

GUSTS.



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 550. MEAN STORM

MOTION VECTOR 26025.





...CORFIDI

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