Severe Weather History


Hazard archive · 1950 — present

Flash Flood in St. Clair County, Illinois

44

Recorded events

0

Direct deaths

0

Direct injuries

$10.1M

Property damage

Flash Flood in St. Clair County, Illinois: 44 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #723 nationally and #15 statewide for this hazard.

Decade by decade

Flash Flood in St. Clair County, Illinois: events per decade

Flash Flood in St. Clair County, Illinois: recorded events per decade
Flash Flood in St. Clair County, Illinois: recorded events per decade

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for flash flood in St. Clair County is the 2000s, when 16 of the county's 44 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.

Within the St. Clair County archive, flash flood makes up 4.9% of all recorded severe weather across 8 hazard types. Nationally the county sits at #723 for this hazard and #15 within Illinois, putting it in the 76.0 percentile of all U.S. counties.

Seasonality

Events by month

0Jan
0Feb
1Mar
5Apr
5May
14Jun
10Jul
6Aug
2Sep
0Oct
0Nov
1Dec

Jun is the peak month for flash flood in St. Clair County with 14 recorded events, while Jan is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.

Most recent

Latest recorded events

DateLocationMagnitudeDamage
Jul 17, 2025SUMMERFIELD0$25K
Jul 6, 2025SUMMERFIELD0$25K
Jul 6, 2025LEBANON0$10K
Apr 5, 2025DARMSTADT0$30K
Jul 15, 2023OAK HILLS0$0
Jul 28, 2022VENICE0$0
Jul 26, 2022EAST CARONDELET0$10.0M
Jul 25, 2021LEMENTON0$0
Aug 12, 2020MILLSTADT0$0
Aug 12, 2020WOODLAND GRANGE0$0
Source: NOAA/NCEI Storm Events · dates UTC · recent entries may be preliminary

Other hazards here

More from St. Clair County

County overview →

From the record

What the reports say

Written by National Weather Service staff at the time of the event · public domain

Quick answers

Frequently asked

How many flash flood events are on record in St. Clair County, Illinois?

44 flash flood events are recorded in St. Clair County between 1996 and 2025, causing 0 direct deaths.

What is the strongest flash flood recorded in St. Clair County?

The strongest flash flood on record in St. Clair County measured 0.

Where does the flash flood data for St. Clair County come from?

All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.

Cite this page

“Flash Flood in St. Clair County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/st-clair-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.


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