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Grundy County, Illinois severe weather history spans 345 recorded events between 1958 and 2026. The dominant hazard is thunderstorm wind, accounting for 54.2% of all recorded events. It ranks #1,520 nationally and #53 in Illinois.
345
Recorded events
0
Direct deaths
16
Direct injuries
$95.1M
Property damage
The record
What the Grundy County, Illinois severe weather history record shows
Across the archive, Grundy County, Illinois severe weather history averages 5.1 recorded events a year. The busiest stretch on record is the 2000s, with 113 events logged in that decade alone. Roughly 32 events fall before 1990 and 313 from 1990 onward — a gap that reflects the expansion of NOAA reporting practice as much as the weather itself.
The costliest is tornado, with $61.9M in reported property damage. In total, 9 distinct hazard types appear in this county archive, each listed with its own dated record below.
By hazard type
Every hazard type recorded in Grundy County
| Hazard | Events | Deaths | Damage | Max | Span |
|---|---|---|---|---|---|
| Thunderstorm Wind | 187 | 0 | $5.5M | 78 | 1960–2025 |
| Hail | 75 | 0 | $605K | 2.75 | 1980–2024 |
| Tornado | 23 | 0 | $61.9M | F2 | 1958–2024 |
| Flood | 22 | 0 | $5.2M | 0 | 2002–2024 |
| Flash Flood | 18 | 0 | $21.6M | 0 | 1996–2026 |
| Lightning | 9 | 0 | $288K | 0 | 2000–2013 |
| Heavy Rain | 9 | 0 | $0 | 0 | 2007–2025 |
| Funnel Cloud | 1 | 0 | $0 | 0 | 2006–2006 |
| Wildfire | 1 | 0 | $0 | 0 | 2003–2003 |
Decade by decade
Grundy County, Illinois severe weather history by decade
Reporting practice changed over time — early decades are undercounted, not calmer.
Tornado tracks
Paths crossing this county
26 mapped tornado paths intersect this county: 21 touched down inside it and 5 crossed in from a neighbouring county. This comes from path geometry, not county-tagged reports.
| Date | Scale | Deaths | Injuries | Path length | Origin |
|---|---|---|---|---|---|
| 2015-06-22 | EF3 | 0 | 7 | 16.3 mi | Touched down here |
| 1972-07-17 | EF3 | 0 | 0 | 81.5 mi | Crossed in |
| 1965-11-12 | EF2 | 2 | 90 | 35.9 mi | Touched down here |
| 2024-07-15 | EF2 | 0 | 2 | 34.6 mi | Touched down here |
| 2016-06-22 | EF2 | 0 | 0 | 8.1 mi | Crossed in |
| 2013-11-17 | EF2 | 0 | 5 | 12.0 mi | Touched down here |
| 1988-04-05 | EF2 | 0 | 0 | 30.0 mi | Touched down here |
| 1975-05-20 | EF2 | 0 | 1 | 2.0 mi | Touched down here |
| 1973-04-19 | EF2 | 0 | 0 | 0.1 mi | Touched down here |
| 1965-11-12 | EF2 | 0 | 0 | 32.1 mi | Crossed in |
Significant events
Deadliest events on record in Grundy County
| Date | Type | Location | Deaths | Injuries | Damage |
|---|---|---|---|---|---|
| Jun 23, 2015 | Tornado | PAYTONVILLE | 0 | 7 | $25.0M |
| Nov 17, 2013 | Tornado | CENTRAL CITY | 0 | 5 | $10.8M |
| May 31, 2000 | Thunderstorm Wind | MAZON | 0 | 2 | $100K |
| May 23, 2020 | Tornado | SANK RIDGE | 0 | 1 | $0 |
| May 20, 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
The tornado touched down near Higgins Road and Dupont Road where softwood trees were snapped. The tornado moved east-southeast where trees and power poles were snapped along N Gorman Road. The most significant damage was noted as the tornado crossed S Carbon Hill Road just south of Division Street, entering Coal City. Dozens of homes were heavily damaged in Coal City with three completely destroyed. Two of these homes were well built and had at least part of their structure bolted down to the foundation with bolts secured by nuts. Two high tension metal trusses were downed including one that was crumpled along Hunters Run. Hundreds of trees were snapped or uprooted. Numerous utility poles were downed. Peak winds were estimated to be 160 mph with a max width of three quarters of a mile. The tornado continued into Will County. (Tornado 8a of 10).
The hardest hit areas in Grundy County were Morris, Mazon, and Minooka. Numerous rescues took place, including people trapped in vehicles in rising waters. Forty-four patients at Morris Hospital were evacuated when the lower floor flooded. The aqueduct that carries the I & M canal over Nettle Creek collapsed. South of Morris, Pine Bluff Road was impassable with approximately a foot of water.
The tornado formed just northwest of the intersection of E Braceville Road and S Carbon Hill Road where several softwood trees were uprooted. The tornado moved northeast just north of E Reed Road where a single family residence sustained visible damage to its exterior while a metal outbuilding sustained roof and exterior wall damage. A single family home sustained considerable damage near the intersection of Berta Road and Spring Road where two people were injured. The tornado continued into a subdivision north of Spring Road where widespread minor damage occurred to several dozen homes. Several homes received more substantial damage though, including partial loss of roofs and second story walls. The tornado continued into Will County around 12:26 PM CST. Maximum wind speeds were estimated to be up to 125 mph.
Context
Risk, population and federal disasters
Relatively Low
FEMA NRI risk rating
53,219
Population (ACS)
$272K
Median home value
15
Federal declarations
| Declared | Incident | Title | Type |
|---|---|---|---|
| Mar 26, 2020 | Biological | COVID-19 PANDEMIC | DR |
| Mar 13, 2020 | Biological | COVID-19 | EM |
| Nov 26, 2013 | Tornado | SEVERE STORMS, STRAIGHT-LINE WINDS, AND TORNADOES | DR |
| May 10, 2013 | Flood | SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING | DR |
| Mar 17, 2011 | Snowstorm | SEVERE WINTER STORM AND SNOWSTORM | DR |
| Oct 3, 2008 | Severe Storm | SEVERE STORMS AND FLOODING | DR |
Within the county
Most affected places
- Morris 106
Quick answers
Frequently asked
How many severe weather events have been recorded in Grundy County, Illinois?
345 events are on record between 1958 and 2026, causing 0 direct deaths and $95.1M in property damage.
What is the most common severe weather hazard in Grundy County?
Thunderstorm Wind, with 187 recorded events — 54.2% of everything in the archive for this county.
How many tornadoes have crossed Grundy County?
26 mapped tornado paths intersect the county boundary; 21 of them touched down inside it. This is derived from path geometry, not county-tagged reports.
How many federal disaster declarations cover Grundy County?
15 federal disaster declarations from FEMA include Grundy County, each tied to a specific incident period.
How risky is Grundy County compared with the rest of the country?
FEMA's National Risk Index rates Grundy County as relatively low risk, placing it in the 67 percentile of its state for expected annual loss.
Where does the Grundy 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
- Greene County 193
- Hamilton County 179
- Gallatin County 239
- Hancock County 510
- Fulton County 617
- Hardin County 87
Cite this page
“Grundy County, Illinois.” Severe Weather History. severeweatherhistory.com/county/illinois/grundy-county/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.