A cold front slowly moved southeast into eastern Iowa during the daytime hours of August 4.  South to southwest winds brought increased heat and humidity with high temperatures that ranged from 82 at Freeport, IL to 99 at Muscatine, IA.  Heat index readings were as high as 120 degrees.
Late that afternoon and evening, an upper level disturbance moved along the cold front triggering showers and thunderstorms over northeast Iowa and northwest Illinois.  Some of the storms produced brief heavy rains, large hail, and damaging winds, with one storm in particular developing a tornado between Charlotte, IA and Goose Lake, IA.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:50:00 to 04-AUG-08 17:50:00 (CST-6)
Location: GERMAN VLY
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 75 mph blew down a 24 inch diameter tree in German Valley, IL at 650 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:30:00 to 04-AUG-08 17:30:00 (CST-6)
Location: GERMAN VLY
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph blew down some 8 to 12 inch diameter tree limbs across German Valley, IL at 630 pm August 4.  A power outage was also observed.

Thunderstorm Wind in CARROLL, ILLINOIS
From 04-AUG-08 17:30:00 to 04-AUG-08 17:30:00 (CST-6)
Location: MILLEDGEVILLE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts estimated to be 60 mph were observed in Milledgeville, IL at 630 pm August 4.  Sustained wind speeds of 40 mph were observed for about ten minutes.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:30:00 to 04-AUG-08 17:55:00 (CST-6)
Location: FREEPORT
Magnitude: 65.00 EG
Property damage: 250.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 to 75 mph caused widespread tree and structural damage in the vicinity of Freeport, IL between 630 pm and 655 pm August 4.  On Rock City Rd, several trees and branches were blown down as well as a metal storage shed.  In addition, twenty-five rows of corn on both sides of the road were flattened.  Some buildings on the southwest side of town were damaged.  On Fairview Rd, a tree was blown over onto a house.  On Edwardsville Rd, some large tree limbs were blown down.  A power outage was also observed across the county.

Thunderstorm Wind in WHITESIDE, ILLINOIS
From 04-AUG-08 17:33:00 to 04-AUG-08 17:33:00 (CST-6)
Location: STERLING
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts estimated to be 65 mph blew down some large tree limbs eight inches in diameter across some roads 2 to 5 miles northeast of Sterling, IL at 633 pm August 4.

Thunderstorm Wind in CARROLL, ILLINOIS
From 04-AUG-08 17:50:00 to 04-AUG-08 17:50:00 (CST-6)
Location: MILLEDGEVILLE
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph blew down some large branches and power lines in Milledgeville, IL at 650 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:50:00 to 04-AUG-08 17:50:00 (CST-6)
Location: GERMAN VLY
Magnitude: 61.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 70 mph blew down a 60 foot HAM radio tower in German Valley, IL at 650 pm August 4.

Thunderstorm Wind in CARROLL, ILLINOIS
From 04-AUG-08 17:00:00 to 04-AUG-08 17:00:00 (CST-6)
Location: SAVANNA
Magnitude: 65.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 75 mph blew down numerous trees and power lines across Carroll County around 600 pm August 4.  Eight trees were blown down at the county fairgrounds, some of which fell on some cars.  Several power outages were observed across the county.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 04-AUG-08 17:10:00 to 04-AUG-08 17:10:00 (CST-6)
Location: STOCKTON
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: COOP Observer

Wind gusts estimated to be 70 mph blew a tree onto a house in Stockton, IL at 610 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:20:00 to 04-AUG-08 17:20:00 (CST-6)
Location: LENA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Wind gusts estimated to be 60 mph blew down some 1 to 2 inch diameter tree branches in Lena, IL at 620 pm August 4.

Thunderstorm Wind in WHITESIDE, ILLINOIS
From 04-AUG-08 18:10:00 to 04-AUG-08 18:10:00 (CST-6)
Location: STERLING ARPT
Magnitude: 61.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts estimated to be 70 mph blew down several 8 to 12 inch diameter trees and telephone poles across Thome Rd 4 miles south of Rock Falls, IL at 710 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:28:00 to 04-AUG-08 17:28:00 (CST-6)
Location: PEARL CITY
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph blew down some utility poles in Pearl City, IL at 628 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:28:00 to 04-AUG-08 17:28:00 (CST-6)
Location: FREEPORT
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph were observed 2 miles west of Freeport, IL at 628 pm August 4.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 04-AUG-08 17:28:00 to 04-AUG-08 17:28:00 (CST-6)
Location: STOCKTON
Magnitude: 56.00 EG
Property damage: 0.20K
Crop damage: 0.00K
Reported by: Broadcast Media

Wind gusts estimated to be 65 mph blew down some five inch diameter tree branches and bent a metal pole supporting a wind sock in half in Stockton, IL at 628 pm August 4.  A metal table was also blown off of a deck.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 04-AUG-08 16:30:00 to 04-AUG-08 16:30:00 (CST-6)
Location: GALENA
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: COOP Observer

Wind gusts estimated to be 60 mph ripped the siding off the west side of a residence 3 miles southeast of Galena, IL at 530 pm August 4.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 04-AUG-08 16:42:00 to 04-AUG-08 16:42:00 (CST-6)
Location: GUILFORD
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts estimated to be 60 mph blew down some branches and small trees 5 miles east of Galena, IL at 542 pm August 4.

Thunderstorm Wind in CARROLL, ILLINOIS
From 04-AUG-08 17:20:00 to 04-AUG-08 17:20:00 (CST-6)
Location: MILLEDGEVILLE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 60 mph blew down some trees and branches in the vicinity of Milledgeville, IL at 620 pm August 4.  A power outage was also observed.  A trained spotter also contributed to this report.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:25:00 to 04-AUG-08 17:25:00 (CST-6)
Location: BOLTON
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph were observed 5 miles southwest of Freeport, IL at 625 pm August 4.

Thunderstorm Wind in STEPHENSON, ILLINOIS
From 04-AUG-08 17:28:00 to 04-AUG-08 17:28:00 (CST-6)
Location: SCIOTA MILLS
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Wind gusts estimated to be 65 mph blew down some utility poles 3 miles north of Freeport, IL at 628 pm August 4.  Heavy rainfall was also observed.