A warm front slowly lifted northward from central Missouri into eastern Iowa and northern Illinois May 12th and 13th.  Several rounds of showers and thunderstorms moved across the area producing widespread torrential rains and some hail. As a result of the heavy rains, flash flooding was common.  There were two corridors of heavy rain; one across Highway 20 with amounts around 2 to 3 inches and a second heavier corridor of 2 to 6 inches from Memphis, Missouri to near Geneseo, Illinois.   Temperatures in the upper 40s to middle 60s on May 12 continued to rise during the early morning hours May 13, reaching into the lower 50s to upper 60s by daybreak.

Flash Flood in HENRY, ILLINOIS
From 13-MAY-10 03:05:00 to 13-MAY-10 07:05:00 (CST-6)
Location: GREEN ROCK
Flood cause: Heavy Rain
Property damage: 5000.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rains resulted in widespread flash flooding of roads and highways across all of Henry County, especially the northwest half during the morning of May 13.

Flash Flood in HANCOCK, ILLINOIS
From 13-MAY-10 05:15:00 to 13-MAY-10 07:15:00 (CST-6)
Location: DALLAS CITY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rains resulted in Camp Creek flooding the intersection of Highway 9 and Highway 94 east of Colusa, IL during the morning of May 13.

Flash Flood in HENDERSON, ILLINOIS
From 12-MAY-10 23:00:00 to 13-MAY-10 03:00:00 (CST-6)
Location: BIG RIVER ST FOREST
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rains flooded some roads across Henderson County during the early morning hours of May 13.

Hail in MCDONOUGH, ILLINOIS
From 12-MAY-10 11:40:00 to 12-MAY-10 11:40:00 (CST-6)
Location: MACOMB
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STEPHENSON, ILLINOIS
From 12-MAY-10 17:04:00 to 12-MAY-10 17:04:00 (CST-6)
Location: LENA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in HANCOCK, ILLINOIS
From 12-MAY-10 21:08:00 to 12-MAY-10 21:08:00 (CST-6)
Location: DALLAS CITY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in JO DAVIESS, ILLINOIS
From 12-MAY-10 17:04:00 to 12-MAY-10 17:04:00 (CST-6)
Location: STOCKTON ARPT
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash Flood in WHITESIDE, ILLINOIS
From 13-MAY-10 02:00:00 to 13-MAY-10 06:00:00 (CST-6)
Location: PENROSE
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Newspaper

The southeast half of Whiteside County received 3 to 4 inches of rain during the early morning hours of May 13 which resulted in some flash flooding.  Several residences in the Sterling and Rock Falls areas reported flooded basements.

Flash Flood in MERCER, ILLINOIS
From 13-MAY-10 03:00:00 to 13-MAY-10 07:00:00 (CST-6)
Location: ELIZA
Flood cause: Heavy Rain
Property damage: 5000.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rains resulted in widespread flash flooding of roads and highways across all of Mercer County, especially the eastern half during the morning of May 13.