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095 

WWUS20 KWNS 211832

SEL0

SPC WW 211832

ILZ000-INZ000-MOZ000-LMZ000-220200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 340

NWS STORM PREDICTION CENTER NORMAN OK

135 PM CDT SAT JUN 21 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN AND WESTERN ILLINOIS

  NORTHWEST INDIANA

  NORTHEAST MISSOURI

  LAKE MICHIGAN



* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 135 PM UNTIL

  900 PM CDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST

NORTHEAST OF ROCKFORD ILLINOIS TO 50 MILES SOUTH OF QUINCY

ILLINOIS.  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.



&&



DISCUSSION...THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON

AHEAD OF AN MESOSCALE VORTICITY CENTER OVER IA.  THESE STORMS WILL

TRACK EASTWARD ACROSS THE WATCH AREA...WITH A RISK OF DAMAGING WIND

GUSTS AND HAIL IN THE STRONGEST CELLS.



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 550. MEAN STORM

MOTION VECTOR 28025.





...HART

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