Thunderstorms developed during the evening hours of July 20th across parts of northern Illinois and continued into the early morning hours of July 21st.  Winds gusted to 60 to 65 mph across parts of Cook county.  An estimated 300 to 400 tress were damaged or blown down in Evergreen Park.  One of the trees fell onto a house in Evergreen Park.  An estimated 50 mature trees were blown down in Naperville.  One of the trees destroyed a backyard playhouse.  A gust to 60 mph was reported in Woodridge in Dupage county, which blew down some tree limbs.  By late evening, thunderstorms redeveloped over parts of northern Illinois producing severe hail.  The largest hail reported was golf ball size hail in Kankakee.  A building suffered roof and structural damage in Ashton in Lee county from winds as high as 75 mph.  Trees were blown down southwest of Polo in Ogle county along Illinois Route 26.  A gust to 64 mph was reported in Sandwich in Dekalb county.  A tree fell onto a house in Mt. Prospect causing some roof damage and lightning hit a mobile home in Elk Grove Village, which blew out the home's wiring and started a fire.  Trees, large tree limbs and power lines were blown down in Sheridan in La Salle county.  Trees and large limbs were blown down in Melvin in Ford county and windows were blown out of some buildings in Melvin.  Two trees were blown down in New Lenox in Will county where a woman was trapped in her car, but not injured.  Trees and large tree limbs were blown down in Fairbury in Livingston county.  Minor flooding was reported in Joliet in Will county.

Thunderstorm Wind in LA SALLE, ILLINOIS
From 21-JUL-03 01:40:00 to 21-JUL-03 01:40:00 (CST)
Location: SHERIDAN
Magnitude: 57 EG
Reported by: LAW ENFORCEMENT

Hail in LAKE, ILLINOIS
From 20-JUL-03 21:15:00 to 20-JUL-03 21:20:00 (CST)
Location: LONG GROVE
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Thunderstorm Wind in DE KALB, ILLINOIS
From 21-JUL-03 01:14:00 to 21-JUL-03 01:14:00 (CST)
Location: SANDWICH
Magnitude: 56 EG
Reported by: AMATEUR RADIO

Thunderstorm Wind in FORD, ILLINOIS
From 21-JUL-03 01:50:00 to 21-JUL-03 01:50:00 (CST)
Location: MELVIN
Magnitude: 52 EG
Reported by: DEPT OF HIGHWAYS

Thunderstorm Wind in COOK, ILLINOIS
From 20-JUL-03 22:00:00 to 20-JUL-03 22:00:00 (CST)
Location: MT PROSPECT
Magnitude: 57 EG
Reported by: NEWSPAPER

Hail in KANKAKEE, ILLINOIS
From 20-JUL-03 21:34:00 to 20-JUL-03 21:39:00 (CST)
Location: KANKAKEE
Magnitude: 1.75 
Reported by: GENERAL PUBLIC

Lightning in COOK, ILLINOIS
From 20-JUL-03 22:00:00 to 20-JUL-03 22:00:00 (CST)
Location: ELK GROVE VLG
Property damage: 25K
Reported by: NEWSPAPER

Thunderstorm Wind in LEE, ILLINOIS
From 21-JUL-03 00:22:00 to 21-JUL-03 00:30:00 (CST)
Location: ASHTON
Magnitude: 65 EG
Reported by: GOVT OFFICIAL

Thunderstorm Wind in OGLE, ILLINOIS
From 21-JUL-03 00:35:00 to 21-JUL-03 00:35:00 (CST)
Location: POLO
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Hail in COOK, ILLINOIS
From 20-JUL-03 21:50:00 to 20-JUL-03 21:55:00 (CST)
Location: PALATINE
Magnitude: 1.00 
Reported by: EMERGENCY MANAGER

Hail in COOK, ILLINOIS
From 20-JUL-03 21:52:00 to 20-JUL-03 21:57:00 (CST)
Location: ARLINGTON HGTS
Magnitude: 0.75 
Reported by: NWS EMPLOYEE(OFF DUTY)

Thunderstorm Wind in WILL, ILLINOIS
From 21-JUL-03 02:03:00 to 21-JUL-03 02:03:00 (CST)
Location: NEW LENOX
Magnitude: 52 EG
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in COOK, ILLINOIS
From 20-JUL-03 17:12:00 to 20-JUL-03 17:12:00 (CST)
Location: EVERGREEN PARK
Magnitude: 57 EG
Reported by: BROADCAST MEDIA

Thunderstorm Wind in DU PAGE, ILLINOIS
From 20-JUL-03 17:10:00 to 20-JUL-03 17:15:00 (CST)
Location: NAPERVILLE
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in COOK, ILLINOIS
From 20-JUL-03 17:04:00 to 20-JUL-03 17:04:00 (CST)
Location: BURBANK
Magnitude: 52 EG
Reported by: TRAINED SPOTTER

Hail in LEE, ILLINOIS
From 20-JUL-03 16:50:00 to 20-JUL-03 17:05:00 (CST)
Location: AMBOY
Magnitude: 0.88 
Reported by: GOVT OFFICIAL

Thunderstorm Wind in LIVINGSTON, ILLINOIS
From 21-JUL-03 01:40:00 to 21-JUL-03 01:40:00 (CST)
Location: FAIRBURY
Magnitude: 57 EG
Reported by: NEWSPAPER

Hail in COOK, ILLINOIS
From 20-JUL-03 21:52:00 to 20-JUL-03 21:57:00 (CST)
Location: DES PLAINES
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in COOK, ILLINOIS
From 20-JUL-03 23:50:00 to 20-JUL-03 23:50:00 (CST)
Location: LANSING
Magnitude: 1.00 
Reported by: GENERAL PUBLIC

Thunderstorm Wind in COOK, ILLINOIS
From 20-JUL-03 17:08:00 to 20-JUL-03 17:08:00 (CST)
Location: HOMETOWN
Magnitude: 52 EG
Reported by: TRAINED SPOTTER

Hail in COOK, ILLINOIS
From 20-JUL-03 22:05:00 to 20-JUL-03 22:15:00 (CST)
Location: LINCOLNWOOD
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Penny size hail was reported along Lincoln Avenue and lasted 10 minutes.