A strong cold front interacting with a highly unstable airmass triggered strong to severe thunderstorms across west-central Illinois during the evening of July 16th.  Scattered wind damage and flash flooding occurred mainly west of the I-55 corridor.  One of the storms produced a short-lived EF-2 tornado that impacted the town of Delavan in Tazewell County, resulting in numerous homes being damaged and two minor injuries.

Thunderstorm Wind in KNOX, ILLINOIS
From 16-JUL-15 18:55:00 to 16-JUL-15 19:00:00 (CST-6)
Location: EAST GALESBURG
Magnitude: 61.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Several power lines were blown down on the east side of Galesburg.

Tornado in TAZEWELL, ILLINOIS
From 16-JUL-15 22:39:00 to 16-JUL-15 22:46:00 (CST-6)
Location: DELAVAN
Tornado F-scale: EF2
Property damage: 1.20M
Crop damage: 10.00K
Reported by: NWS Storm Survey

A tornado touched down 0.6 miles south of Delavan at 11:39 PM CDT.  The tornado then moved east-northeast across the south side of Delavan, damaging 51 homes.  15 of the homes sustained severe damage, including either the roofs being completely torn off or the majority of the roof deck being lifted off.  Numerous garages, outbuildings, and trees were damaged.  The tornado also crossed through the Prairie Rest Cemetery, damaging grave markers and several trees before dissipating in a cornfield 2.2 miles east-northeast of Delavan at 11:46 PM CDT.

Thunderstorm Wind in KNOX, ILLINOIS
From 16-JUL-15 19:00:00 to 16-JUL-15 19:05:00 (CST-6)
Location: KNOXVILLE
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous power lines were blown down in Knoxville.

Thunderstorm Wind in FULTON, ILLINOIS
From 16-JUL-15 19:57:00 to 16-JUL-15 20:05:00 (CST-6)
Location: NORRIS
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Corn crops were blown over just north of Norris.

Thunderstorm Wind in TAZEWELL, ILLINOIS
From 16-JUL-15 23:25:00 to 16-JUL-15 23:30:00 (CST-6)
Location: ARMINGTON
Magnitude: 61.00 EG
Property damage: 12.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several trees were blown down in Armington.

Thunderstorm Wind in LOGAN, ILLINOIS
From 16-JUL-15 23:28:00 to 16-JUL-15 23:33:00 (CST-6)
Location: ATLANTA
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Public

Several large trees were blown down and a tin roof was blown off an outbuilding.

Flash Flood in KNOX, ILLINOIS
From 16-JUL-15 19:30:00 to 17-JUL-15 01:00:00 (CST-6)
Location: (GBG)GALESBURG ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Severe thunderstorms produced 2.00 to 4.00 inches of rain in less than three hours during the evening of July 16th in west central and southern Knox County. The resultant flash flooding produced extensive street flooding in parts of Galesburg. Rural roads were flooded and impassable in spots from Abingdon to Maquon and from Galesburg to Knoxville.

Flash Flood in TAZEWELL, ILLINOIS
From 16-JUL-15 22:30:00 to 17-JUL-15 04:30:00 (CST-6)
Location: MIDWAY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Severe thunderstorms produced 4.00 to 6.00 inches of rain in less than three hours in central and southern Tazewell County during the late evening of July 16th. The heavy rain produced flash flooding which resulted in parts of I-155 from mile post 15 to 22 being impassable. Numerous rural roads were closed from South Pekin to Hopedale to Armington. The flooding of these roads hampered rescue efforts in the immediate aftermath of the tornado which impacted the town of Delavan. The flooding subsided a couple of hours before daybreak.