Tornadoes · United States · Illinois
Tornadoes in DeKalb County, Illinois
31 tornadoes have crossed DeKalb County since 1950, 1 of them surveyed so far this year and still preliminary, 56th of the 102 counties in Illinois with a tornado on record, an average of one every 2.5 years. They have killed 2 people and injured 12. 1 was rated F4 or EF4 and above.
The rating scale
Tracks are drawn in the color of the rating. The United States rated tornadoes on Ted Fujita’s F scale until 31 January 2007 and on the Enhanced Fujita scale after it. Both run from 0 to 5, and both rate the damage rather than measure the wind: the speeds are what that damage is taken to imply.
F0 / EF040 to 72 mph on the F scale, 65 to 85 mph on the EF scale
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F1 / EF173 to 112 mph on the F scale, 86 to 110 mph on the EF scale
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
F2 / EF2113 to 157 mph on the F scale, 111 to 135 mph on the EF scale
Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.
F3 / EF3158 to 206 mph on the F scale, 136 to 165 mph on the EF scale
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
F4 / EF4207 to 260 mph on the F scale, 166 to 200 mph on the EF scale
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
F5 / EF5261 to 318 mph on the F scale, over 200 mph on the EF scale
Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.
Unrated
The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.
Now
- Tornadoes
- 31
- Deaths
- 2
- Injuries
- 12
- F4 and above
- 1
- Worst on record
- EF4, April 9, 2015
The deadliest in DeKalb County
The strongest
Every year with a tornado
The 19 years of the 76 in the record with a tornado in DeKalb County. Each year links to every tornado in Illinois that year.
Every tornado that crossed DeKalb County
31 tornadoes, newest first. The 1 at the top is this year's, from the surveying office rather than SPC's published database, and its rating is marked as preliminary.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| June 11, 2026 | 7:01 PM CDT | Unrated | Lee | 6.0 | 50 | |||
| July 15, 2024 | 8:38 PM CDT | Unrated | DeKalb | 1.8 | 50 | |||
| July 14, 2024 | 8:58 PM CDT | EF0 | DeKalb | 3.4 | 100 | |||
| February 27, 2024 | 6:53 PM CST | EF0 | DeKalb | 5.4 | 175 | |||
| February 27, 2024 | 6:28 PM CST | Unrated | DeKalb | 1.3 | 120 | |||
| July 28, 2023 | 10:32 PM CDT | EF0 | Kendall | 0.8 | 20 | |||
| August 10, 2021 | 6:33 PM CDT | Unrated | DeKalb | 0.6 | 20 | |||
| August 9, 2021 | 6:26 PM CDT | EF0 | DeKalb | 0.2 | 20 | |||
| August 9, 2021 | 6:13 PM CDT | EF1 | DeKalb | 1.5 | 150 | |||
| August 9, 2021 | 5:28 PM CDT | EF0 | DeKalb | 6.8 | 50 | |||
| August 9, 2021 | 4:44 PM CDT | EF1 | DeKalb | 1.8 | 80 | |||
| August 9, 2021 | 4:35 PM CDT | EF0 | DeKalb | 0.1 | 20 | |||
| November 10, 2020 | 4:19 PM CST | EF0 | DeKalb | 10.0 | 50 | |||
| August 10, 2020 | 2:50 PM CDT | EF0 | DeKalb | 6.3 | 40 | |||
| May 23, 2020 | 6:06 PM CDT | EF0 | Kane | 3.2 | 50 | |||
| April 9, 2015 | 7:15 PM CDT | EF1 | Boone | 4.0 | 100 | $80,000 | ||
| April 9, 2015 | 6:39 PM CDT | EF4 | Rochelle–Fairdale tornado | 30.1 | 700 | 2 | 11 | $19 million |
| June 12, 2013 | 4:32 PM CDT | EF1 | DeKalb | 2.3 | 100 | $20,000 | ||
| May 13, 2011 | 1:30 PM CDT | EF0 | DeKalb | 0.1 | 50 | |||
| August 24, 2004 | 5:55 PM CDT | F0 | DeKalb | 2.8 | 100 | $20,000 | ||
| May 10, 2004 | 5:30 PM CDT | F0 | DeKalb | 0.2 | 10 | |||
| June 10, 2003 | 6:30 PM CDT | F0 | DeKalb | 0.5 | 50 | |||
| May 10, 2001 | 10:10 PM CDT | F0 | DeKalb | 0.1 | 20 | |||
| June 6, 1996 | 4:15 PM CDT | F0 | DeKalb | 2.0 | 20 | |||
| May 18, 1982 | 6:27 PM CDT | F0 | DeKalb | 0.1 | 10 | |||
| June 30, 1977 | 9:45 AM CDT | F1 | DeKalb | 1.6 | 90 | $5,000 to $50,000 | ||
| June 18, 1975 | 1:00 PM CDT | F2 | DeKalb | 4.7 | 27 | 1 | $50,000 to $500,000 | |
| May 14, 1972 | 12:40 PM CDT | F0 | DeKalb | 0.1 | 10 | |||
| April 21, 1967 | 4:40 PM GMT-6 | F1 | DeKalb | 2.0 | 40 | $5,000 to $50,000 | ||
| July 10, 1959 | 9:00 PM GMT-5 | F1 | DeKalb | 1.0 | 60 | $5,000 to $50,000 | ||
| August 15, 1958 | 3:00 AM GMT-5 | F2 | Lee | 74.5 | 100 | $50,000 to $500,000 |
Nearby
Warnings in force in DeKalb CountyThe forecast for DeKalb CountyThe live radar over DeKalb CountyEvery county in Illinois
What this means
Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.