Widely scattered thunderstorms developed during the afternoon of May 26th.  Due to an extremely moist environment and weak steering winds aloft, the storms were slow-moving in nature and produced copious amounts of rainfall.  Between 4 and 5 inches of rain fell in Springfield in about 90 minutes, causing widespread flash-flooding which impacted hundreds of homes, businesses, and autos.  In addition, some of the other storms in central and east central Illinois produced large hail, damaging wind gusts and flash flooding.

Flash Flood in VERMILION, ILLINOIS
From 26-MAY-10 17:00:00 to 26-MAY-10 21:00:00 (CST-6)
Location: RANKIN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A slow moving thunderstorm produced 2.50 inches of rain in one hour in a small part of northwest Vermilion County. Many rural roads were inundated around the town of Rankin, including a small part of Illinois Route 9 and Illinois Route 49.

Flash Flood in DOUGLAS, ILLINOIS
From 26-MAY-10 16:30:00 to 26-MAY-10 21:30:00 (CST-6)
Location: ARCOLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Slow moving thunderstorms produced 2.50 inches of rain in one hour across a small part of southern Douglas County. Many roads were impassable, including a 1 mile stretch of I-57 for a short time, between the county line and the town of Arcola.

Hail in SANGAMON, ILLINOIS
From 26-MAY-10 14:49:00 to 26-MAY-10 14:50:00 (CST-6)
Location: SPRINGFIELD
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Golfball sized hail was reported on the west side of Springfield on Old Jacksonville Road.

Hail in SANGAMON, ILLINOIS
From 26-MAY-10 15:03:00 to 26-MAY-10 15:13:00 (CST-6)
Location: JEROME
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail covered the ground.

Hail in SANGAMON, ILLINOIS
From 26-MAY-10 15:45:00 to 26-MAY-10 16:05:00 (CST-6)
Location: SPRINGFIELD
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail lasted for 20 minutes.

Thunderstorm Wind in SCOTT, ILLINOIS
From 26-MAY-10 15:45:00 to 26-MAY-10 15:46:00 (CST-6)
Location: GLASGOW
Magnitude: 52.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A small shed was blown over.

Hail in CHAMPAIGN, ILLINOIS
From 26-MAY-10 17:05:00 to 26-MAY-10 17:25:00 (CST-6)
Location: ROYAL
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Hail accumulated several inches deep, causing significant damage to a corn field northeast of Royal.

Flash Flood in CHAMPAIGN, ILLINOIS
From 26-MAY-10 17:30:00 to 26-MAY-10 21:00:00 (CST-6)
Location: DILLSBURG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A slow moving thunderstorm produced 2.50 inches of rain in one hour across part of northeast Champaign County. Most rural roads were impassable because of the flooding.

Flash Flood in SANGAMON, ILLINOIS
From 26-MAY-10 14:30:00 to 26-MAY-10 23:30:00 (CST-6)
Location: GRANDVIEW
Flood cause: Heavy Rain
Property damage: 9.75M
Crop damage: 0.00K
Reported by: Emergency Manager

A nearly stationary thunderstorm produced around 4.50 inches of rain in 90 minutes over the city of Springfield just before the evening rush hour. The downtown suffered major impacts with extensive flooding of streets and up to 7 feet of water under viaducts. Most streets were impassable, which resulted in more than 200 stranded vehicles. Nearly 650 homes and businesses sustained flood damage. Several people had to be rescued from the their flooded autos, but there were no injuries or fatalities.

Flash Flood in SCOTT, ILLINOIS
From 26-MAY-10 16:00:00 to 26-MAY-10 21:00:00 (CST-6)
Location: WINCHESTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Slow moving thunderstorms produced 3.00 to 4.00 inches of rain in 2 hours across southern Scott County. Many rural roads were impassable, including Illinois Route 106 from Alsey to the Greene County line.

Flash Flood in COLES, ILLINOIS
From 26-MAY-10 16:30:00 to 26-MAY-10 21:30:00 (CST-6)
Location: HUMBOLDT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Slow moving thunderstorms produced 2.50 inches of rain in one hour across a small part of northern Coles County. Many roads were impassable, including a 3 mile stretch of I-57 for a short time, between the county line and the town of Humboldt.

Thunderstorm Wind in CHAMPAIGN, ILLINOIS
From 26-MAY-10 17:05:00 to 26-MAY-10 17:25:00 (CST-6)
Location: ROYAL
Magnitude: 52.00 EG
Property damage: 12.00K
Crop damage: 0.00K
Reported by: NWS Employee

Several houses had windows blown out from thunderstorm winds.

Hail in SCOTT, ILLINOIS
From 26-MAY-10 15:45:00 to 26-MAY-10 15:46:00 (CST-6)
Location: GLASGOW
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement