A cold front stretching across the upper Midwest, coupled with warm moist air streaming northward across the area, brought scattered showers and isolated thunderstorms to portions of east central Iowa and northern Illinois during the midday hours August 9. Some locations along the Highway 20 corridor saw rainfall amounts ranging from 1 to 2 inches from these storms. Afternoon high temperatures were in the upper 80s to lower 90s.
By late afternoon, showers and thunderstorms began to redevelop along the cold front in western Iowa and spread eastward into the Mid-Mississippi Valley.
During the evening hours, these storms brought widespread rain to the Mid-Mississippi Valley. In addition, several of these storms became severe over eastern Iowa producing winds gusts from 50 to 80 mph around the Cedar Rapids Area.

Thunderstorm Wind in WARREN, ILLINOIS
From 09-AUG-09 19:33:00 to 09-AUG-09 19:33:00 (CST-6)
Location: LITTLE YORK
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 tree limbs in Little York, IL around 833 pm August 9.

Thunderstorm Wind in HENDERSON, ILLINOIS
From 09-AUG-09 19:45:00 to 09-AUG-09 19:45:00 (CST-6)
Location: ROZETTA
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 about 2 miles east of Oquawka, IL around 845 pm August 9.

Thunderstorm Wind in HENDERSON, ILLINOIS
From 09-AUG-09 20:00:00 to 09-AUG-09 20:00:00 (CST-6)
Location: BALD BLUFF
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts estimated to be 50 to 60 mph were observed about 5 miles northeast of Oquawka, IL around 900 pm August 9.

Flash Flood in WARREN, ILLINOIS
From 09-AUG-09 20:03:00 to 09-AUG-09 22:00:00 (CST-6)
Location: LITTLE YORK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rains resulted in some flash flooding of parts of Warren County during the late evening of August 9.  Flood waters covered several roads in the vicinity of Little York, IL.  Flood waters were 1 to 1.5 feet deep over a portion of Route 135 about 1.5 miles south of Little York, IL.

Thunderstorm Wind in JO DAVIESS, ILLINOIS
From 09-AUG-09 12:52:00 to 09-AUG-09 12:52:00 (CST-6)
Location: APPLE RIVER
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 several 10 to 12 inch diameter tree limbs in Apple River, IL around 152 pm August 9.

Flash Flood in JO DAVIESS, ILLINOIS
From 09-AUG-09 21:45:00 to 09-AUG-09 23:45:00 (CST-6)
Location: COUNCIL HILL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rains resulted in flash flooding of some roads in the vicinity of Guilford, IL during the late evening of August 9.

Flash Flood in HENDERSON, ILLINOIS
From 09-AUG-09 20:52:00 to 09-AUG-09 22:52:00 (CST-6)
Location: BIG RIVER ST FOREST
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rains resulted in some flash flooding of parts of Henderson County during the late evening of August 9.  Parts of Highways 94 and 164 were under water in the Oquawka, IL area.

Flash Flood in JO DAVIESS, ILLINOIS
From 09-AUG-09 13:15:00 to 09-AUG-09 18:00:00 (CST-6)
Location: COUNCIL HILL STATION
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: COOP Observer

Heavy rains caused some flash flooding in parts of Jo Daviess County during the afternoon and evening of August 9.  Some roads and culverts near Scales Mound, IL were washed out and Small Pox Creek flooded out of its banks forcing the closure of several roads.