A stationary frontal boundary interacting with an unseasonably moist airmass triggered several clusters of thunderstorms across north-central Illinois during the morning of May 30th.  Locally heavy rainfall of 3 to 5 inches occurred from eastern Peoria County across portions of Tazewell, Marshall, and Woodford counties.  Due to excessive rainfall rates, flash flooding was reported in many areas.  Route 17 became impassable when Gimlet Creek overflowed onto the roadway near Sparland in Marshall County.  A mudslide occurred at Grosenbach Road and Route 116 in Woodford County near the Illinois River.  In addition, numerous county roads had water flowing across them and manhole covers were displaced by high water in Pekin in Tazewell County.

Flash Flood in MARSHALL, ILLINOIS
From 30-MAY-18 07:30:00 to 30-MAY-18 11:30:00 (CST-6)
Location: BROADMOOR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain of 2.50 to 4.50 inches, most of which fell in less than two hours during the early morning hours, resulted in rapid flash flooding in Marshall County along and west of the Illinois River. Numerous county roads west of Sparland and Hopewell were impassable. Part of Illinois Route 17 west of Sparland was flooded when Gimlet Creek rose out of its banks. The flooding subsided by afternoon.

Flash Flood in WOODFORD, ILLINOIS
From 30-MAY-18 08:00:00 to 30-MAY-18 11:30:00 (CST-6)
Location: SPRING BAY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain of 2.00 to 3.00 inches, most of which fell in less than two hours during the early morning hours, resulted in rapid flash flooding in western Woodford County along and just east of the Illinois River. Several roads along the Illinois River were impassable, including parts of Illinois Route 26 from just south of Spring Bay to the Tazewell County line. The flooding subsided by afternoon.

Flash Flood in TAZEWELL, ILLINOIS
From 30-MAY-18 07:30:00 to 30-MAY-18 11:30:00 (CST-6)
Location: TRAIL PARK GARDENS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain of 2.00 to 4.00 inches, most of which fell in a two hour period during the early morning hours, resulted in rapid flash flooding in northwest and central Tazewell County. Numerous streets were impassable in Pekin and East Peoria, as were several county roads from west of Morton, through Tremont to Delavan. A mudslide was reported between East Peoria and Germantown Hills at Illinois Route 116 and Grosenbach Road, which closed roads for several hours. Officials reported several manhole covers blown off in Pekin. The flooding subsided by afternoon.

Flash Flood in PEORIA, ILLINOIS
From 30-MAY-18 07:30:00 to 30-MAY-18 11:30:00 (CST-6)
Location: EDELSTEIN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Heavy rain of 2.00 to 4.00 inches, most of which fell in less than two hours during the early morning hours, resulted in rapid flash flooding in extreme eastern Peoria County. Numerous roads were impassable along the Illinois River, particularly in Mossville and Chillicothe. Several streets in downtown Peoria also had standing water. The flooding subsided by afternoon.