Tornadoes · United States · Iowa

Tornadoes in Harrison County, Iowa

36 tornadoes have crossed Harrison County since 1950, 1 of them surveyed so far this year and still preliminary, 48th of the 99 counties in Iowa with a tornado on record, an average of one every 2.1 years. They have killed 7 people and injured 76. 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.

  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
36
Deaths
7
Injuries
76
F4 and above
1
Worst on record
EF4, April 26, 2024

The deadliest in Harrison County

  1. EF3, Harrison and Monona counties, IowaJune 11, 20084 killed, 48 injured
  2. F3, Harrison County, IowaMay 16, 19992 killed, 16 injured
  3. EF3 Minden–Harlan tornado, IowaApril 26, 20241 killed, 3 injured

The strongest

  1. EF4 Elkhorn tornado, Nebraska and IowaApril 26, 2024EF4, 31.9 mi (51 km)
  2. EF3 Minden–Harlan tornado, IowaApril 26, 2024EF3, 40.3 mi (65 km)
  3. F3, Harrison and Crawford counties, IowaJune 16, 1992F3, 26.0 mi (42 km)
  4. EF3, Douglas, Pottawattamie and Harrison counties, Iowa and NebraskaApril 26, 2024EF3, 19.1 mi (31 km)
  5. EF3, Harrison and Monona counties, IowaJune 11, 2008EF3, 13.0 mi (21 km)
  6. F3, Harrison County, IowaMay 16, 1999F3, 7.5 mi (12 km)
  7. F3, Harrison County, IowaMay 16, 1999F3, 6.2 mi (10 km)
  8. F2, Harrison County, IowaMay 6, 1983F2, 15.0 mi (24 km)
  9. F2, Pottawattamie and Harrison counties, IowaMay 6, 1975F2, 12.8 mi (21 km)
  10. F2, Harrison and Pottawattamie counties, IowaMay 6, 1975F2, 10.6 mi (17 km)

Every year with a tornado

The 23 years of the 76 in the record with a tornado in Harrison County. Each year links to every tornado in Iowa that year.

YearTornadoesDeathsInjuriesStrongest
20261EF1
2024717EF4
20231EF2
20222EF1
20191Unrated
20161EF0
201122EF1
20091EF2
20081448EF3
20041F0
20021F0
20011F0
20001F1
19992216F3
199223F3
19912F1
19871F0
19842F1
19831F2
19801F1
19752F2
19721F2
19671F1

Every tornado that crossed Harrison County

36 tornadoes, newest first. 2 of them touched down in a neighboring state and ran in, so the record files them under that state rather than Iowa. 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.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 23, 20261:46 PM CDTEF1Harrison2.9500
May 24, 20242:41 AM CDTEF1Harrison0.7150
April 26, 20245:40 PM CDTEF1Harrison1.830
April 26, 20245:25 PM CDTEF3Minden–Harlan tornado40.31,90013
April 26, 20244:59 PM CDTEF0Harrison2.6200
April 26, 20244:54 PM CDTEF3Douglas to NE19.1550
April 26, 20244:52 PM CDTEF1Harrison9.1766
April 26, 20243:30 PM CDTEF4Elkhorn tornado31.91,9004
July 12, 20236:05 AM CDTEF2Harrison9.4100
April 12, 20228:25 PM CDTEF0Harrison2.3200
April 12, 20228:08 PM CDTEF1Harrison9.6140
September 24, 20195:57 PM CDTUnratedHarrison0.125
June 29, 20165:51 PM CDTEF0Harrison3.325
June 26, 20117:55 PM CDTEF0Harrison3.6100
March 22, 20115:00 PM CDTEF1Harrison11.71002
March 23, 20096:03 PM CDTEF2Harrison8.6440
June 11, 20086:27 PM CDTEF3Harrison13.0440448
May 22, 20048:19 PM CDTF0Harrison0.260
April 17, 20026:29 PM CDTF0Harrison2.025
June 18, 20017:59 PM CDTF0Harrison0.225
June 13, 20003:10 PM CDTF1Harrison10.6330$30,000
May 16, 19994:16 PM CDTF3Harrison7.5440216$1.9 million
May 16, 19993:45 PM CDTF3Harrison6.2200$100,000
June 16, 19929:30 PM CDTF3Harrison26.02003$500,000 to $5 million
May 16, 19929:15 PM CDTF0Harrison0.113$500 to $5,000
June 14, 19918:55 PM CDTF0Harrison0.220$500 to $5,000
April 29, 19911:20 PM CDTF1Pottawattamie20.040$50,000 to $500,000
June 12, 19877:50 PM CDTF0Harrison0.520$500 to $5,000
June 17, 19847:43 PM CDTF0Harrison0.110$500 to $5,000
June 17, 19847:14 PM CDTF1Burt to IA14.030$50,000 to $500,000
May 6, 19836:00 PM CDTF2Harrison15.020$50,000 to $500,000
May 29, 198010:00 PM CDTF1Harrison1.030$5,000 to $50,000
May 6, 19755:20 PM CDTF2Harrison10.610$5,000 to $50,000
May 6, 19755:00 PM CDTF2Pottawattamie12.8500$5,000 to $50,000
September 12, 19724:30 PM CDTF2Harrison5.9100$5,000 to $50,000
June 20, 196712:00 AM GMT-5F1Harrison0.110$5,000 to $50,000

Nearby

Warnings in force in Harrison CountyThe forecast for Harrison CountyThe live radar over Harrison CountyEvery county in Iowa

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.