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Monroe County, Illinois severe weather history spans 315 recorded events between 1957 and 2026. The dominant hazard is thunderstorm wind, accounting for 40.3% of all recorded events. It ranks #1,696 nationally and #60 in Illinois.
315
Recorded events
0
Direct deaths
2
Direct injuries
$3.4M
Property damage
The record
What the Monroe County, Illinois severe weather history record shows
Across the archive, Monroe County, Illinois severe weather history averages 4.6 recorded events a year. The busiest stretch on record is the 2010s, with 88 events logged in that decade alone. Roughly 34 events fall before 1990 and 281 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The costliest is tornado, with $2.2M in reported property damage. In total, 6 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Monroe County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 127 | 0 | $1.2M | 87 | 1968–2025 |
| Hail | 120 | 0 | $11K | 2.75 | 1971–2026 |
| Tornado | 41 | 0 | $2.2M | F3 | 1957–2026 |
| Flash Flood | 19 | 0 | $1K | 0 | 1996–2022 |
| Flood | 6 | 0 | $0 | 0 | 1997–2019 |
| Heavy Rain | 2 | 0 | $0 | 0 | 2003–2005 |
Decade by decade
Monroe County, Illinois severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
45 mapped tornado paths intersect this county: 39 touched down inside it and 6 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 2006-03-11 | EF3 | 0 | 0 | 5.1 mi | Crossed in |
| 1975-04-18 | EF3 | 0 | 1 | 2.0 mi | Touched down here |
| 2011-04-22 | EF2 | 0 | 1 | 3.5 mi | Touched down here |
| 2010-04-30 | EF2 | 0 | 0 | 7.2 mi | Touched down here |
| 1995-05-18 | EF2 | 0 | 0 | 4.0 mi | Touched down here |
| 1995-05-18 | EF2 | 0 | 0 | 4.2 mi | Touched down here |
| 1973-05-07 | EF2 | 0 | 0 | 0.5 mi | Touched down here |
| 1968-04-03 | EF2 | 0 | 0 | 19.8 mi | Touched down here |
| 1960-03-29 | EF2 | 0 | 0 | 22.3 mi | Crossed in |
| 1957-05-21 | EF2 | 0 | 0 | 19.7 mi | Touched down here |
Significant events
Deadliest events on record in Monroe County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Apr 23, 2011 | Tornado | WATERLOO | 0 | 1 | $0 |
| Apr 18, 1975 | Tornado | 0 | 1 | $250K |
From the record
What the reports say
Written by National Weather Service staff at the time of the event · public domain
A small tornado touched down in the northwest corner of Waterloo damaging a four-story brick grain elevator. Damage was generally confined to the building's roof (along the eastern side). As the tornado moved east-northeast through a residential area, damage was limited to large trees. A large cluster of trees were snapped off near the town high school in a rotational pattern. A house lost part of its roof northeast of Waterloo just before the tornado dissipated.
At approximately 9:52 PM a tornado began southwest of Valmeyer, IL in Monroe County and continued northeast where it impacted the towns of Valmeyer and Waterloo. The worst damage was to residences and small businesses within these municipalities. From Waterloo the tornado moved into a rural area where it produced minor tree damage along the Monroe/St. Clair County border. In Monroe County the tornado was rated EF-1 with a path length of 12.3 miles and maximum path width of 275 yards.
Thunderstorm wind gusts caused damage at a couple of farms on Griggs Road in southeast Monroe County. A couple of machine sheds were destroyed, damaging the tractors and other farm equipment inside. Some silos and grain bins were also damaged.
Context
Risk, population and federal disasters
Very Low
FEMA NRI risk rating
35,036
Population (ACS)
$282K
Median home value
20
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Aug 15, 2023 | Severe Storm | SEVERE STORMS AND FLOODING | DR |
| Mar 26, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Sep 19, 2019 | Flood | SEVERE STORMS AND FLOODING | DR |
| May 10, 2013 | Flood | SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING | DR |
| Jun 24, 2008 | Severe Storm | SEVERE STORMS AND FLOODING | DR |
Quick answers
Frequently asked
How many severe weather events have been recorded in Monroe County, Illinois?
315 events are on record between 1957 and 2026, causing 0 direct deaths and $3.4M in property damage.
What is the most common severe weather hazard in Monroe County?
Thunderstorm Wind, with 127 recorded events — 40.3% of everything in the archive for this county.
How many tornadoes have crossed Monroe County?
45 mapped tornado paths intersect the county boundary; 39 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Monroe County?
20 federal disaster declarations from FEMA include Monroe County, each tied to a specific incident period.
How risky is Monroe County compared with the rest of the country?
FEMA's National Risk Index rates Monroe County as very low risk, placing it in the 42 percentile of its state for expected annual loss.
Where does the Monroe County, Illinois severe weather history data come from?
Every figure is drawn from United States federal public-domain records: NOAA/NCEI Storm Events for the event archive, NOAA SPC SVRGIS for mapped tornado paths, FEMA for disaster declarations and risk ratings, and the U.S. Census for population context. Dates are shown in UTC and recent entries may still be revised by NOAA.
Nearby
Neighbouring counties
- Mercer County 341
- Montgomery County 417
- Menard County 258
- Morgan County 371
- Massac County 300
- Moultrie County 192
Cite this page
“Monroe County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/monroe-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.