

173 

WWUS20 KWNS 200425

SEL5

SPC WW 200425

ILZ000-WIZ000-LMZ000-200800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 665

NWS STORM PREDICTION CENTER NORMAN OK

1125 PM CDT TUE JUL 19 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST ILLINOIS

       SOUTHEAST WISCONSIN

       LAKE MICHIGAN



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1125 PM

UNTIL 300 AM 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 60 MILES NORTH

NORTHEAST OF MADISON WISCONSIN TO 15 MILES SOUTH SOUTHWEST OF

MEIGS FIELD ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



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 664...



DISCUSSION...A MATURE BOW ECHO OVER CENTRAL WI WILL TRACK RAPIDLY

SOUTHEASTWARD ACROSS THE WATCH AREA THROUGH THE EARLY MORNING HOURS.

 A VERY UNSTABLE AIR MASS AND SUFFICIENT FLOW ALOFT WILL MAINTAIN

THE RISK OF DAMAGING WINDS ALONG THE LEADING EDGE OF THE LINE OF

STORMS.



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 32040.





...HART

