Flash Flood — Mclean, Illinois

2021-06-25 to 2021-06-26 · near Stanford, Mclean, Illinois

Event narrative

Numerous roads were closed due to flood waters, including Route 136 between Heyworth and McLean. Part of the I-55 shoulder collapsed near Kickapoo Creek southwest of Bloomington, prompting the closure of the interstate. A dive team from Hudson was deployed to rescue a stranded motorist on I-55 southwest of Shirley. Other vehicles were stranded by high water near mile marker 159 on I-55 near Bloomington, at exit 142 on I-74 near the Kickapoo Creek Bridge just west of Downs, and about 2 miles north of LeRoy. A homeowner was stranded by high water surrounding their property a mile north of Heyworth. Nearly 1, 600 homes and 75 businesses were damaged by the flooding, including more than 200 structures that had major damage or were destroyed.

Wider weather episode

A series of disturbances tracking along a nearly stationary frontal boundary resulted in two periods of heavy rainfall across parts of central Illinois on June 25th and June 26th. The hardest hit areas were across southern McLean County into far northern Logan County, as well as across southern portions of Scott and Morgan counties. The first wave of heavy rain began around 7pm CDT June 25th and persisted until around 11pm that evening before tapering off. Rainfall amounts across southern McLean County ranged from 4 to 7 inches in 4 hours, with the heaviest rain extending from near the town of McLean through Bloomington-Normal southeastward toward LeRoy. The second wave of heavy rain occurred during the afternoon of June 26th when additional amounts of 2 to 4 inches fell across the same areas of southern McLean County that had been impacted the previous evening. Storm total rainfall between 6pm CDT June 25th and 6pm CDT June 26th ranged from 6 to 11 inches across southern McLean County, with a maximum amount of 10.71 inches measured 1.5 miles east-southeast of Bloomington...which represented a 1,000-year rainfall (0.1 percent chance of occurring in any given year). Locations from Funks Grove through Shirley to southern and eastern parts of Bloomington experienced a 500-year rainfall (0.2 percent chance of occurring in any given year). Due to the tremendous amount of rainfall, significant flash flooding occurred across central and southern McLean County into far northern Logan County, including the city of Bloomington. Numerous roads were closed due to high water, several water rescues needed to be performed due to stranded motorists, part of the I-55 shoulder collapsed near Kickapoo Creek, and Kickapoo Creek reached record levels and flooded several homes in Lawndale in far northern Logan County.

View location on OpenStreetMap → (40.4547, -89.2381)

Source: NOAA Storm Events Database, event_id 962039. Narrative written by the NWS forecast office that issued the report.