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Flood in Monroe County, Illinois
31 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.
NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. Storm records through 30 Jun 2026.
NCEI records 31 flood events in Monroe County, Illinois, between 1950 and 2026, spread over 18 years.
May is the busiest month, with 9 of the recorded events. The last 20 years account for 18 events against 13 in the 20 years before, a change that reflects reporting practice as much as weather.
The county holds 0.5% of the 6,507 flood events recorded in Illinois; its 8.0 per 100 square miles compares with 11.7 statewide.
Compared with Illinois
| Measure | Monroe County | Illinois | US |
|---|---|---|---|
| Flood events since 1950 | 31 | 6,507 | 183,559 |
| Per 100 square miles | 8.0 | 11.7 | 5.2 |
| Per 10,000 residents | 8.9 | 5.1 | 5.5 |
| Deaths recorded | 0 | 61 | 2,961 |
| Busiest month | May | June | June |
By year
Seasonality
0Feb
0Mar
0Apr
6May
9Jun
6Jul
3Aug
3Sep
2Oct
1Nov
0Dec
1
Recorded events
All 31 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.
| Date | Event type | Magnitude | Property damage | Crop damage | Deaths | Injuries | Geography |
|---|---|---|---|---|---|---|---|
| 3 Aug 2022 | Flash Flood | — | — | — | — | — | County |
| 12 Aug 2020 | Flash Flood | — | — | — | — | — | County |
| 2 Jun 2019 | Flood | — | — | — | — | — | County |
| 7 Sep 2018 | Flash Flood | — | — | — | — | — | County |
| 19 Oct 2016 | Flash Flood | — | — | — | — | — | County |
| 11 May 2016 | Flash Flood | — | — | — | — | — | County |
| 19 Jun 2015 | Flash Flood | — | — | — | — | — | County |
| 3 Apr 2014 | Flash Flood | — | — | — | — | — | County |
| 18 Apr 2013 | Flash Flood | — | — | — | — | — | County |
| 7 Jul 2011 | Flash Flood | — | — | — | — | — | County |
| 22 Apr 2011 | Flash Flood | — | — | — | — | — | County |
| 22 Apr 2011 | Flash Flood | — | — | — | — | — | County |
| 27 Jul 2010 | Flash Flood | — | — | — | — | — | County |
| 16 Jun 2010 | Flood | — | — | — | — | — | County |
| 27 Dec 2008 | Flash Flood | — | — | — | — | — | County |
| 14 Sep 2008 | Flood | — | — | — | — | — | County |
| 4 Jun 2008 | Flood | — | — | — | — | — | County |
| 25 May 2008 | Flash Flood | — | $1K | $5K | — | — | County |
| 27 May 2004 | Flash Flood | — | — | — | — | — | County |
| 6 May 2003 | Flash Flood | — | — | — | — | — | County |
| 12 May 2002 | Flash Flood | — | — | — | — | — | County |
| 1 May 2002 | Flood | — | — | — | — | — | Forecast zone |
| 1 May 2002 | Flood | — | — | — | — | — | Forecast zone |
| 28 Apr 2002 | Flood | — | — | — | — | — | Forecast zone |
| 4 Jun 2001 | Flood | — | — | — | — | — | Forecast zone |
| 9 May 2001 | Flood | — | — | — | — | — | Forecast zone |
| 5 Aug 1998 | Flood | — | — | — | — | — | County |
| 27 Jul 1997 | Flood | — | — | — | — | — | County |
| 22 Jun 1997 | Flash Flood | — | — | — | — | — | County |
| 1 May 1996 | Flood | — | — | — | — | — | Forecast zone |
| 28 Apr 1996 | Flash Flood | — | — | — | — | — | County |
Questions and answers
How many flood events has Monroe County had?
31 events in the NCEI Storm Events record between 1950 and 2026. Reporting of floods and flash floods became far more complete after 1996, so early decades undercount.
When was the last recorded flood event in Monroe County?
3 Aug 2022 (Flash Flood). Records reach NCEI about 120 days after the month ends.
What was the most damaging flood event recorded in Monroe County?
The flash flood of 25 May 2008, with property damage estimated by NCEI at $1K and crop damage at $5K.
How does Monroe County compare with Illinois for flood?
8.0 events per 100 square miles against 11.7 statewide; the county holds 31 of the state's 6,507 recorded events.
Provenance
NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026, public domain. County-recorded events plus zone-recorded events whose forecast zone is named for the county (marked "Forecast zone"). Population and area from the US Census Bureau (2021). Built 1 Oct 2026. See the methodology, the Flood hub and the county page.