

000 

WWUS20 KWNS 190030

SEL6

SPC WW 190030

ILZ000-INZ000-MIZ000-LMZ000-190800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 536

NWS STORM PREDICTION CENTER NORMAN OK

730 PM CDT WED JUL 18 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN ILLINOIS

       NORTHERN INDIANA

       SOUTHERN LOWER MICHIGAN

       LAKE MICHIGAN



EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 730 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES WEST

SOUTHWEST OF MEIGS FIELD ILLINOIS TO 20 MILES EAST NORTHEAST OF

FORT WAYNE INDIANA.  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.



OTHER WATCH INFORMATION...CONTINUE...WW 529...WW 531...WW

532...WW 533...WW 534...WW 535...



DISCUSSION...TSTMS/POSSIBLE EMBEDDED SUPERCELLS EXPECTED TO

CONTINUING DEVELOPING E/SE ALONG WARM ADVECTION WING ASSOCIATED WITH

ERN IA MCS.  SUFFICIENT SHEAR AND LOW LEVEL MOISTURE ARE PRESENT FOR

A BRIEF TORNADO OR TWO...BUT EXPECTED QUASI-LINEAR STORM MODE AND

EVENTUAL ARRIVAL OF FORWARD-PROPAGATING/BOWING PART OF IA SYSTEM

EXPECTED TO KEEP WIND/HAIL THE PRIMARY SVR THREATS.



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 30035.





...CORFIDI

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