

868 

WWUS20 KWNS 170201

SEL7

SPC WW 170201

IAZ000-ILZ000-170800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 307

NWS STORM PREDICTION CENTER NORMAN OK

900 PM CDT MON JUN 16 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  EAST CENTRAL IOWA

  NORTHWEST ILLINOIS



* EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 900 PM

  UNTIL 300 AM CDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH LIKELY

  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE

  A TORNADO OR TWO POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST OF

CEDAR RAPIDS IOWA TO 65 MILES EAST NORTHEAST OF MOLINE ILLINOIS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 303...WW 304...WW

305...WW 306...



DISCUSSION...WELL-DEVELOPED MCS WITH SOME EMBEDDED SUPERCELL

STRUCTURES WILL CONTINUE TO MOVE ESEWD/SEWD ACROSS ERN IA/NW

IL...ALONG THE INSTABILITY GRADIENT.  THE MAIN RISK WITH THESE

STORMS WILL BE DAMAGING WINDS...BUT A TORNADO OR TWO CANNOT BE RULED

OUT WITH LEADING EDGE CIRCULATIONS.  THE STRONGER EMBEDDED STORMS

MAY ALSO PRODUCE ISOLATED LARGE HAIL.



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 29030.





...THOMPSON

