Tornadoes · United States · Illinois

Tornadoes in Stephenson County, Illinois

21 tornadoes have crossed Stephenson County since 1950, 71st of the 102 counties in Illinois with a tornado on record, an average of one every 3.6 years. They have killed 1 person and injured 0. None was rated F4 or 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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
21
Deaths
1
Injuries
0
F4 and above
0
Worst on record
F2, October 8, 1958

The deadliest in Stephenson County

The strongest

Every year with a tornado

The 13 years of the 76 in the record with a tornado in Stephenson County. Each year links to every tornado in Illinois that year.

YearTornadoesDeathsInjuriesStrongest
20243EF2
20231EF1
20221EF1
20201EF0
20172EF1
20101EF0
20091EF0
20033F0
19992F0
19983F1
19711F1
19591F1
195811F2

Every tornado that crossed Stephenson County

21 tornadoes, newest first.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 15, 20247:26 PM CDTUnratedStephenson1.010
July 15, 20246:50 PM CDTEF2Jo Daviess15.4150
March 4, 20241:59 PM CSTUnratedStephenson0.130
March 31, 20236:50 PM CDTEF1Carroll11.0200
May 25, 20223:06 PM CDTEF1Stephenson1.830
August 10, 20202:12 PM CDTEF0Stephenson4.650
August 16, 20177:28 PM CDTEF0Stephenson3.320
August 16, 20177:21 PM CDTEF1Stephenson2.875
July 12, 20104:03 PM CDTEF0Stephenson0.125
June 1, 20094:30 PM CDTEF0Stephenson0.3200$100,000
June 14, 20034:03 PM CDTF0Stephenson0.050
June 14, 20033:30 PM CDTF0Stephenson0.550
June 14, 20033:15 PM CDTF0Stephenson0.050
June 6, 19993:14 PM CDTF0Stephenson0.110
June 1, 19996:50 PM CDTF0Stephenson0.110
August 24, 199812:30 PM CDTF1Stephenson0.550$80,000
May 28, 19988:46 PM CDTF0Stephenson0.130$1,000
May 28, 19988:23 PM CDTF0Stephenson0.130
June 1, 19716:15 PM CDTF1Stephenson0.110$50,000 to $500,000
April 17, 19592:00 PM GMT-6F1Stephenson2.010$5,000 to $50,000
October 8, 195812:30 AM GMT-5F2Stephenson81.0101$500,000 to $5 million

Nearby

Warnings in force in Stephenson CountyThe forecast for Stephenson CountyThe live radar over Stephenson 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.