Several clusters of strong to severe thunderstorms developed across central Illinois in advance of a cold front during the afternoon and evening of June 22nd. Some of the storms produced damaging wind gusts of around 60mph and locally heavy downpours.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS ILX wrote it up.
Several clusters of strong to severe thunderstorms developed across central Illinois in advance of a cold front during the afternoon and evening of June 22nd. Some of the storms produced damaging wind gusts of around 60mph and locally heavy downpours. Flash flooding was observed across portions of Macon, Christian, Piatt, and Champaign counties.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Lincoln, IL wrote its last area forecast discussion before the first event at Jun 22, 11:54 AM CST, 2 hours 30 minutes earlier.
Area Forecast Discussion National Weather Service Lincoln IL 1254 PM CDT Mon Jun 22 2020 .SYNOPSIS... Issued at 1110 AM CDT Mon Jun 22 2020 Scattered thunderstorms are possible this afternoon and evening, as a cold front moves into the area. Locally heavy rain, gusty winds, and dangerous lightning area possible. Dry weather is expected for Tuesday and Wednesday, along with cooler and less humid conditions. && .UPDATE... Issued at 1110 AM CDT Mon Jun 22 2020 Upper trof was pushing into IA/MO late this morning with several shortwaves noted on water vapor imagery. At the surface, 1009 mb low pressure was analyzed along the front in northwest MO. Outflow from an earlier thunderstorm complex which grazed the far northwest CWA had pushed near a Danville to St. Louis line at 11 am. This will likely be a focus for isolated/scattered thunderstorm development through early afternoon. Beyond that we expect to see an overall increase in thunderstorm coverage by mid to late afternoon, as forcing increases ahead of the wave and front to the west. Modest shear and mid level lapse rates will promote some stronger storms, with pulse downburst wind gusts being the main severe threat. Slow storm motion and an increasing PW airmass (1.8-1.9" by 00z) will lead to a locally heavy rain threat with the stronger storms, capable of dumping a couple inches of rain in less than one hour. Raised highs a few degrees into the upper 80s except mid 80s northwest of the IL River. With dewpoints near 70F, peak afternoon heat indices will reach 90-95. && .SHORT TERM...(Today and tonight) ISSUED AT 311 AM CDT Mon Jun 22 2020 Starting the morning off dry across central and southeast Illinois, although some light patchy fog has begun to develop across southeast Illinois this morning. This should spread across southeastern Illinois and some locations in eastern Illinois, as current reports indicate much of Indiana under patchy fog. This is due to the clear skies, and abundant sfc moisture evaporating, and is expected to burn off quickly after sunrise. Looking at radar trends over the past few hours, watching a developing cluster of storms in northern MO and south central IA. These continue a slow ene progression, and should track across the Mississippi through the morning. Some of this storms are expected to clip portions of the CWA, mainly ne of the IL River Valley. Model depiction has this line lifting into northern IL through the morning, holding dry conditions in place throughout much of the coverage area. As the cold front begins to approach the Midwest this afternoon, expecting shower and storm activity to ramp up and overspread the region. A Marginal Risk for severe storms covers the entire ILX CWA today, with the main threats being wind damage and hail. With saturated soils, and the numerous areas of water lingering from the past couple of days, some flooding could occur today with storms. This system will finally push through the region tonight, bringing cooler air to the region, along with drier conditions. .LONG TERM...(Tuesday through Sunday) ISSUED AT 311 AM CDT Mon Jun 22 2020 With the cooler air filtering in, highs are only forecast in the upper 70s to low 80s Tuesday and Wednesday. Also expecting lower Td values, which will bring relief in terms of atmospheric moisture across the region. Unfortunately, the Low pressure system in the upper levels does not quickly exit the area behind fropa. The sfc Low will lift through the lower Great Lakes region into eastern Canada by Wednesday morning, however with the cyclonic rotation, light moisture could be ushered through the upper Midwest into the local area Tuesday afternoon. This could bring light drizzle or showers to the region, mainly along and northeast of I-74. This pattern will also hold clouds overhead of the region, aiding the cooler temperatures around the Midwest through mid-week. Warmer conditions begin to return during the second half of the work week. Again with the continuation of weak upper level cyclonic pattern flow, as the Low slides ne, chances for light precip will linger into the second half of the week. These chances will be limited, however cannot rule out the possibility. High pressure tries to ridge into se US late week, but will be over- powered by the flattening pattern due to another approaching Low pressure system from the western US. This looks to track through the central Plains next weekend, bringing another sfc Low through the upper Plains/Midwest. It appears the ridge will provide some directional movement of next weekend's precip...however this will need to be monitored for changes, which could bring more precip into the region with a southerly track. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 1254 PM CDT Mon Jun 22 2020 A couple of boundaries will be the focus for convective development in central and eastern IL this afternoon through the evening. A weak outflow boundary from early morning t-storms extended from just east of Taylorville toward KCMI-KIKK. Isolated showers and t-storms have already developed along this boundary, and will continue to do so as the atmosphere continues to become more unstable early this afternoon. In addition, low pressure in southeast IA was along a front that extended from eastern Iowa through central MO. This front will advance toward central IL early this evening, and into eastern IL by late evening. This will be the main focusing mechanism for t-storms and periodic MVFR conditions, mainly due to lower visibility in moderate/heavy showers. Transitioned all of the t-storms out of central IL between 02-04z, and in eastern IL by 06z. Should see some lingering showers behind the front, along with MVFR ceilings after 06z. Increasing subsidence behind the front and increasing northwest winds after daybreak should break up the ceilings and return conditions to VFR levels. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && UPDATE...25 SYNOPSIS...25 SHORT TERM...Baker LONG TERM...Baker AVIATION...Miller
Hazardous Weather Outlook National Weather Service Lincoln IL 1201 PM CDT Mon Jun 22 2020 ILZ027>031-036>038-040>057-061-231715- Cass-Champaign-Christian-Coles-De Witt-Douglas-Edgar-Fulton-Knox- Logan-Macon-Marshall-Mason-McLean-Menard-Morgan-Moultrie-Peoria- Piatt-Sangamon-Schuyler-Scott-Shelby-Stark-Tazewell-Vermilion- Woodford- 1201 PM CDT Mon Jun 22 2020 This Hazardous Weather Outlook is for portions of central Illinois, east central Illinois and west central Illinois. .DAY ONE...THIS AFTERNOON AND TONIGHT... Scattered thunderstorms will affect the area this afternoon and evening. Some of the storms could be severe, with damaging winds and hail the main threats. Very heavy rainfall will also be possible. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY... Periodic thunderstorms are possible Friday through Sunday. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed this afternoon and this evening. Please relay any information about observed severe weather to the National Weather Service while following all local, state and CDC guidelines. ILZ062-063-066>068-071>073-231715- Clark-Clay-Crawford-Cumberland-Effingham-Jasper-Lawrence-Richland- 1201 PM CDT Mon Jun 22 2020 This Hazardous Weather Outlook is for portions of east central Illinois and southeast Illinois. .DAY ONE...THIS AFTERNOON AND TONIGHT... Scattered thunderstorms will affect the area this afternoon and tonight. Some of the storms could be strong to severe this afternoon and this evening, with strong winds and hail the main threats. Very heavy rainfall will also be possible. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY... Periodic thunderstorms are possible Friday through Sunday. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed this afternoon and this evening. Please relay any information about observed severe weather to the National Weather Service while following all local, state and CDC guidelines. 25
The Lincoln radar (KILX), 73 km away, was scanning. The volume nearest the first event began at 20:21 UTC.
8 thunderstorm wind, 7 flash flood. Local standard time, as filed.
A tree was blown onto a house.
Three power poles were snapped.
A semi was blown over on northbound I-55 near Divernon.
Three 12-inch diameter 20-foot long trees were blown down onto a driveway.
Several large tree limbs were blown down onto a road.
Two 1.5 to 2-foot diameter trees were blown down. One of the trees fell onto a fence.
Several trees were blown down in Galesburg.
Several trees were blown down in East Galesburg.
Water was flowing over numerous roads in and around Harristown.
A few viaducts were flooded in Decatur.
Water was flowing across a road on the northwest side of Stonington. The road was barricaded to prevent traffic.
Street flooding occurred on Cottonwood and Eden Road northwest of Hanna City.
Water was flowing across Route 128 just north of Shelbyville.
Parts of Highway 150 were flooded and barricaded from the Piatt County border eastward to Mahomet.
Parts of Highway 150 were flooded from Mansfield eastward to the Champaign County border.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2020Every state in 2020This day in weather historyWarnings in Illinois, June 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 896157, 896159, 896161, 896162, 896163, 896164, 896166, 896167, 896147, 896168, 896153, 896172, 896155, 896174, 896173.