Tornadoes · United States · Iowa

Tornadoes in Hamilton County, Iowa

56 tornadoes have crossed Hamilton County since 1950, 10th of the 99 counties in Iowa with a tornado on record, an average of one every 1.4 years. They have killed 1 person and injured 13. 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
56
Deaths
1
Injuries
13
F4 and above
1
Worst on record
F4, May 24, 1989

The deadliest in Hamilton County

  1. F3, Boone, Webster and Hamilton counties, IowaNovember 12, 20051 killed, 3 injured

The strongest

  1. F4, Hamilton, Story, Hardin and Marshall counties, IowaMay 24, 1989F4, 66.0 mi (106 km)
  2. F3, Boone, Webster and Hamilton counties, IowaNovember 12, 2005F3, 17.6 mi (28 km)
  3. F2, Webster, Hamilton and Wright counties, IowaJune 7, 1953F2, 49.0 mi (79 km)
  4. F2, Boone and Hamilton counties, IowaMarch 13, 1990F2, 22.0 mi (35 km)
  5. EF2, Boone, Webster and Hamilton counties, IowaDecember 15, 2021EF2, 16.3 mi (26 km)
  6. EF2, Hamilton and Webster counties, IowaDecember 15, 2021EF2, 12.1 mi (19 km)
  7. F2, Hamilton and Wright counties, IowaMay 17, 1991F2, 9.0 mi (14 km)
  8. F2, Hamilton County, IowaJune 28, 1979F2, 7.2 mi (12 km)
  9. F2, Hamilton County, IowaJune 28, 1979F2, 1.0 mi (2 km)
  10. F2, Hamilton County, IowaJune 22, 1974F2, 0.1 mi (0 km)

Every year with a tornado

The 26 years of the 76 in the record with a tornado in Hamilton County. Each year links to every tornado in Iowa that year.

YearTornadoesDeathsInjuriesStrongest
20242EF1
20216EF2
20181EF0
201411EF1
20092EF0
20081EF0
20071EF0
2005513F3
20041F0
20031F0
20011F1
19992F0
19941F0
19921F0
19912F2
19903F2
19892F4
19871F1
19802F1
1979310F2
19741F2
19671F1
19661F1
19641F0
19631F1
19532F2

Every tornado that crossed Hamilton County

56 tornadoes, newest first.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 24, 20245:10 AM CDTEF1Hamilton2.975$80,000
April 7, 20243:50 PM CDTEF1Hamilton0.770$20,000
December 15, 20216:01 PM CSTEF0Hamilton7.680$70,000
December 15, 20216:01 PM CSTEF0Hamilton8.870$10,000
December 15, 20215:55 PM CSTEF2Hamilton12.1100$180,000
December 15, 20215:49 PM CSTEF2Boone16.3125$105,000
July 14, 20214:21 PM CDTEF1Hamilton8.9160$10,000
July 14, 20214:05 PM CDTEF0Hamilton8.850$2,000
July 19, 20182:56 PM CDTEF0Hamilton2.760
August 31, 20149:08 PM CDTEF1Hamilton2.6150$110,000
August 31, 20149:06 PM CDTEF0Hamilton1.260
August 31, 20148:59 PM CDTEF0Hamilton4.6120$25,000
August 31, 20148:58 PM CDTEF0Hamilton1.575
August 31, 20148:46 PM CDTEF0Hamilton5.265
August 31, 20148:43 PM CDTEF1Boone5.0150$10,000
August 31, 20148:43 PM CDTEF0Hamilton3.9240$1,000
August 31, 20148:41 PM CDTEF0Hamilton5.6110
August 31, 20148:40 PM CDTEF1Webster4.6205
July 6, 20146:03 PM CDTEF0Hamilton0.625
June 29, 20147:28 PM CDTEF0Hamilton2.040
June 21, 20095:36 PM CDTEF0Hamilton0.530
June 21, 20094:48 PM CDTEF0Hamilton1.430
April 24, 20088:21 PM CDTEF0Hamilton1.750$50,000
June 1, 20076:30 PM CDTEF0Hamilton0.130
November 12, 20055:27 PM CSTF0Hamilton1.530$10,000
November 12, 20055:20 PM CSTF1Story8.075$730,000
November 12, 20054:27 PM CSTF3Boone17.615013$12 million
May 18, 20058:38 PM CDTF0Hamilton0.220$10,000
March 30, 200512:51 PM CSTF0Hamilton0.230
September 5, 20047:15 PM CDTF0Hamilton0.220
July 9, 20035:44 PM CDTF0Hamilton0.225
April 11, 20013:38 PM CDTF1Hamilton2.250$70,000
June 6, 19997:15 PM CDTF0Hamilton0.120
June 6, 19997:05 PM CDTF0Hamilton0.20
June 6, 19948:08 PM CDTF0Hamilton0.323$50 to $500
July 15, 19927:43 PM CDTF0Hamilton0.120$500 to $5,000
May 17, 19914:10 PM CDTF0Hamilton0.117$500 to $5,000
May 17, 19912:00 PM CDTF2Hamilton9.060$5,000 to $50,000
July 11, 19905:04 PM CDTF0Hamilton0.113$500 to $5,000
June 19, 19906:45 AM CDTF1Hamilton6.550$50,000 to $500,000
March 13, 19907:25 PM CSTF2Boone22.050$500,000 to $5 million
July 17, 198910:00 PM CDTF1Hamilton5.040$500 to $5,000
May 24, 19896:20 PM CDTF4Hamilton66.0150$5 million to $50 million
July 8, 19874:25 PM CDTF1Hamilton1.023$5,000 to $50,000
October 16, 19806:30 PM CDTF1Boone9.030$50,000 to $500,000
May 29, 19809:45 PM CDTF1Hamilton0.130$5,000 to $50,000
August 19, 19797:32 PM CDTF1Hamilton4.7100$5,000 to $50,000
June 28, 19799:20 PM CDTF2Hamilton1.0177$50,000 to $500,000
June 28, 19799:01 PM CDTF2Hamilton7.235010$50,000 to $500,000
June 22, 19742:25 AM CDTF2Hamilton0.1100$50,000 to $500,000
June 7, 19674:10 PM GMT-5F1Hamilton0.110$5,000 to $50,000
October 15, 19663:00 PM GMT-5F1Hamilton0.110$5,000 to $50,000
August 27, 196410:00 PM GMT-5F0Hamilton1.050$5,000 to $50,000
May 3, 19638:40 PM GMT-5F1Hamilton1.9200$5,000 to $50,000
June 7, 195310:30 PM GMT-5F1Boone2.3100
June 7, 195310:00 PM GMT-5F2Webster49.0200

Nearby

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