[LeArc] Weather Watch : 7@ 7/27/2003 11:31:27 AM

[learc@mailman.qth.net]

The following weather message is provided by McDonough County E.S.D.A.


WWUS20 KWNS 271630
SEL7  
SPC WW 271630
ILZ000-INZ000-MIZ000-LMZ000-272200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 807 
NWS STORM PREDICTION CENTER NORMAN OK 
1130 AM CDT SUN JUL 27 2003

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 

       NORTHERN ILLINOIS
       NORTHERN INDIANA
       EXTREME SOUTHWEST LOWER MICHIGAN
       LAKE MICHIGAN

EFFECTIVE THIS SUNDAY MORNING AND AFTERNOON FROM 1130 AM UNTIL 500
PM CDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 55 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 30 MILES NORTH OF PEORIA ILLINOIS
TO 15 MILES EAST NORTHEAST OF FORT WAYNE INDIANA.

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...THUNDERSTORM CLUSTER MOVING INTO NW IL WILL LIKELY
INCREASE IN COVERAGE/INTENSITY THE NEXT FEW HOURS AS THE LOW LEVELS
DESTABILIZE IN ADVANCE OF THE STORMS ACROSS NRN IL/INDIANA.  MLCAPE
VALUES SHOULD INCREASE TO 2000-2500 J/KG BY EARLY-MID
AFTERNOON...WHILE THE CAP WEAKENS ALONG AND S OF A SWD MOVING COLD
FRONT ACROSS NRN IL AND LOWER MI.  MODERATE INSTABILITY AND ROUGHLY
30 KT MID LEVEL FLOW WILL SUPPORT THE THREAT FOR DAMAGING WINDS AND
ISOLATED LARGE HAIL WITH THE ONGOING IL STORM CLUSTER...AND
ADDITIONAL STORM DEVELOPMENT IS EXPECTED BY EARLY AFTERNOON ACROSS
NRN INDIANA.

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 27035.


...THOMPSON

;415,0894 415,0845 401,0845 401,0894; 

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