Earlier in the afternoon, a line of severe thunderstorms rolled across much of northern Illinois. These storms were well in advance of a strong cold front approaching from the central plains. By evening, this cold front had moved into eastern Iowa, and a second line of severe thunderstorms developed across the same area, with much of the same results. Very strong thunderstorm winds caused damage across a large portion of northern and north central Illinois during the evening. In Winnebago County  tree limbs were downed, especially in the northern part of the county.  In Belvidere, Boone County large trees were blown down damaging automobiles and homes. In Ogle County a cooperative observer in Polo reported trees down and shingles ripped off a roof. Branches were blown down from Byron to Oregon as well.  Trees were blown down in the northern part of DeKalb County at Kirkland, Genoa and Kingston. Gusty winds and tree damage was reported in parts of McHenry and Lake Counties. A semi-tractor trailer was blown over on Interstate 57 in Chebanse, and a funnel cloud was sighted along Interstate 55 near Braidwood and tree damage occurred in Braidwood. On the outskirts of Mazon a microburst destroyed a grain bin and tool shed, with a second grain bin severly damaged. Nearby fields of corn were flattend down in a southward direction, and a couple of telephone poles were snapped about five feet above the ground. The worst hail was reported in the community of Rutland, where several vehicles were damaged by golfball size hail.  Elsewhere in LaSalle County  large trees were blown down in Seneca and high winds were also reported in Marseilles and Tonica.  Limbs were down at several locations in Kankakee County.

Hail in KENDALL, ILLINOIS
From 11-SEP-00 21:11:00 to 11-SEP-00 21:11:00 (CST)
Location: PLANO
Magnitude: 0.75 
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in BOONE, ILLINOIS
From 11-SEP-00 19:54:00 to 11-SEP-00 19:54:00 (CST)
Location: BELVIDERE
Magnitude: 60 E
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in OGLE, ILLINOIS
From 11-SEP-00 19:24:00 to 11-SEP-00 19:24:00 (CST)
Location: POLO
Magnitude: 60 E
Reported by: LAW ENFORCEMENT

Hail in OGLE, ILLINOIS
From 11-SEP-00 19:40:00 to 11-SEP-00 19:40:00 (CST)
Location: ROCHELLE
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in LA SALLE, ILLINOIS
From 11-SEP-00 21:30:00 to 11-SEP-00 21:30:00 (CST)
Location: TONICA
Magnitude: 58 E
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in LA SALLE, ILLINOIS
From 11-SEP-00 21:25:00 to 11-SEP-00 21:25:00 (CST)
Location: MARSEILLES
Magnitude: 58 M
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in OGLE, ILLINOIS
From 11-SEP-00 19:45:00 to 11-SEP-00 19:45:00 (CST)
Location: BYRON
Magnitude: 60 E
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in LA SALLE, ILLINOIS
From 11-SEP-00 21:28:00 to 11-SEP-00 21:28:00 (CST)
Location: SENECA
Magnitude: 65 M
Reported by: AMATEUR RADIO

Thunderstorm Wind in OGLE, ILLINOIS
From 11-SEP-00 19:45:00 to 11-SEP-00 19:45:00 (CST)
Location: OREGON
Magnitude: 58 E
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in MCHENRY, ILLINOIS
From 11-SEP-00 20:27:00 to 11-SEP-00 20:27:00 (CST)
Location: ALGONQUIN
Magnitude: 60 M
Reported by: AMATEUR RADIO

Hail in DE KALB, ILLINOIS
From 11-SEP-00 20:50:00 to 11-SEP-00 20:50:00 (CST)
Location: DE KALB
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Thunderstorm Wind in LAKE, ILLINOIS
From 11-SEP-00 20:30:00 to 11-SEP-00 20:30:00 (CST)
Location: WAUKEGAN
Magnitude: 63 M
Reported by: METEOROLOGIST(NON NWS)

Thunderstorm Wind in KANKAKEE, ILLINOIS
From 11-SEP-00 22:00:00 to 11-SEP-00 22:15:00 (CST)
Location: COUNTYWIDE
Magnitude: 50 E
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in WINNEBAGO, ILLINOIS
From 11-SEP-00 19:15:00 to 11-SEP-00 19:15:00 (CST)
Location: DURAND
Magnitude: 50 E
Reported by: DEPT OF HIGHWAYS

Thunderstorm Wind in WILL, ILLINOIS
From 11-SEP-00 22:00:00 to 11-SEP-00 22:00:00 (CST)
Location: BRAIDWOOD
Magnitude: 50 E
Reported by: EMERGENCY MANAGER

Hail in LA SALLE, ILLINOIS
From 11-SEP-00 21:55:00 to 11-SEP-00 21:55:00 (CST)
Location: RUTLAND
Magnitude: 1.75 
Reported by: AMATEUR RADIO

Thunderstorm Wind in GRUNDY, ILLINOIS
From 11-SEP-00 21:35:00 to 11-SEP-00 21:35:00 (CST)
Location: MORRIS
Magnitude: 65 M
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in IROQUOIS, ILLINOIS
From 11-SEP-00 22:17:00 to 11-SEP-00 22:17:00 (CST)
Location: CHEBANSE
Magnitude: 70 E
Reported by: AMATEUR RADIO

Funnel Cloud in WILL, ILLINOIS
From 11-SEP-00 22:07:00 to 11-SEP-00 22:07:00 (CST)
Location: BRAIDWOOD
Reported by: EMERGENCY MANAGER

Hail in LIVINGSTON, ILLINOIS
From 11-SEP-00 22:30:00 to 11-SEP-00 22:30:00 (CST)
Location: PONTIAC
Magnitude: 0.75 
Reported by: FIRE DEPT/RESCUE SQUAD

Thunderstorm Wind in MCHENRY, ILLINOIS
From 11-SEP-00 20:15:00 to 11-SEP-00 20:15:00 (CST)
Location: MARENGO
Magnitude: 58 E
Reported by: EMERGENCY MANAGER

Thunderstorm Wind in GRUNDY, ILLINOIS
From 11-SEP-00 21:35:00 to 11-SEP-00 21:35:00 (CST)
Location: MAZON
Magnitude: 70 E
Property damage: 50K
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in DE KALB, ILLINOIS
From 11-SEP-00 20:15:00 to 11-SEP-00 20:15:00 (CST)
Location: KIRKLAND
Magnitude: 58 E
Reported by: LAW ENFORCEMENT