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Iroquois County, Illinois severe weather history spans 433 recorded events between 1954 and 2026. The dominant hazard is thunderstorm wind, accounting for 53.8% of all recorded events. It ranks #1,122 nationally and #37 in Illinois.
433
Recorded events
0
Direct deaths
15
Direct injuries
$17.8M
Property damage
The record
What the Iroquois County, Illinois severe weather history record shows
Across the archive, Iroquois County, Illinois severe weather history averages 6.0 recorded events a year. The busiest stretch on record is the 2000s, with 132 events logged in that decade alone. Roughly 61 events fall before 1990 and 372 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The costliest is tornado, with $9.2M in reported property damage. In total, 8 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Iroquois County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 233 | 0 | $1.6M | 87 | 1958–2026 |
| Hail | 73 | 0 | $305K | 3 | 1960–2024 |
| Tornado | 61 | 0 | $9.2M | F3 | 1954–2026 |
| Flood | 26 | 0 | $4.5M | 0 | 1998–2023 |
| Flash Flood | 25 | 0 | $2.1M | 0 | 1996–2023 |
| Funnel Cloud | 8 | 0 | $0 | 0 | 2010–2025 |
| Heavy Rain | 5 | 0 | $0 | 0 | 2019–2025 |
| Lightning | 2 | 0 | $100K | 0 | 2000–2005 |
Decade by decade
Iroquois County, Illinois severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
61 mapped tornado paths intersect this county: 52 touched down inside it and 9 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 1976-03-12 | EF3 | 1 | 15 | 38.5 mi | Touched down here |
| 2013-11-17 | EF3 | 0 | 6 | 29.8 mi | Crossed in |
| 1968-05-15 | EF3 | 0 | 0 | 7.1 mi | Touched down here |
| 1956-03-06 | EF3 | 0 | 6 | 9.4 mi | Touched down here |
| 1992-06-17 | EF2 | 0 | 1 | 0.1 mi | Touched down here |
| 1990-06-22 | EF2 | 0 | 0 | 3.0 mi | Crossed in |
| 1976-04-23 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1976-04-23 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1975-05-24 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1973-03-31 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
Significant events
Deadliest events on record in Iroquois County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Mar 6, 1956 | Tornado | 0 | 6 | $250K | |
| Sep 10, 1992 | Thunderstorm Wind | 0 | 2 | $0 | |
| Sep 15, 1965 | Tornado | 0 | 2 | $25K | |
| May 31, 1954 | Tornado | 0 | 2 | $250K | |
| Jan 8, 2008 | Flash Flood | MILFORD | 0 | 1 | $15K |
| Oct 30, 1996 | Thunderstorm Wind | COUNTYWIDE | 0 | 1 | $0 |
| Jun 17, 1992 | 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
Heavy rain which fell onto saturated and frozen ground on January 8th caused widespread and significant flooding across much of Iroquois County. The county was declared a disaster area and over 600 residents had to be evacuated. Many homes and businesses were flooded as well as hundreds of roads that were flooded and closed. Storm total rainfall included 3.27 inches in Milford and 3.10 inches in Watseka.
Major flooding occurred along the Iroquois River. The river crested at 26.06 feet at Iroquois on February 22nd, which was the second highest crest on record. Flood stage at Iroquois is 18 feet and major stage is 25 feet. The river crested at 20.59 feet at Chebanse on February 24th, which was also the second highest crest on record. Flood stage at Chebanse is 16 feet and major stage is 20 feet.||In the city of Watseka, over 100 homes suffered some kind of water damage from the flooding. Businesses and ground floor apartments were also flooded. Numerous roads were closed. Some residents had to be rescued by boats. The emergency manager said this flooding was likely the worst the city has seen.
In Milford, the Route 1 viaduct was flooded and closed. In Cissna Park, widespread flooding was reported with numerous flooded and closed roads. Some people were evacuated from their homes. Significant flooding was also reported in Watseka.
Context
Risk, population and federal disasters
Relatively Low
FEMA NRI risk rating
26,449
Population (ACS)
$138K
Median home value
9
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Mar 26, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Mar 7, 2008 | Severe Storm | SEVERE STORMS AND FLOODING | DR |
| Sep 7, 2005 | Hurricane | HURRICANE KATRINA EVACUATION | EM |
| May 21, 2002 | Tornado | SEVERE STORMS, TORNADOES AND FLOODING | DR |
| Jan 17, 2001 | Snowstorm | ILLINOIS WINTER SNOW STORMS | EM |
Quick answers
Frequently asked
How many severe weather events have been recorded in Iroquois County, Illinois?
433 events are on record between 1954 and 2026, causing 0 direct deaths and $17.8M in property damage.
What is the most common severe weather hazard in Iroquois County?
Thunderstorm Wind, with 233 recorded events — 53.8% of everything in the archive for this county.
How many tornadoes have crossed Iroquois County?
61 mapped tornado paths intersect the county boundary; 52 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Iroquois County?
9 federal disaster declarations from FEMA include Iroquois County, each tied to a specific incident period.
How risky is Iroquois County compared with the rest of the country?
FEMA's National Risk Index rates Iroquois County as relatively low risk, placing it in the 74 percentile of its state for expected annual loss.
Where does the Iroquois 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
- Henry County 679
- Jackson County 578
- Henderson County 223
- Jasper County 231
- Hardin County 87
- Jefferson County 335
Cite this page
“Iroquois County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/iroquois-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.