Tornadoes · United States · Iowa

Tornadoes in Marshall County, Iowa

39 tornadoes have crossed Marshall County since 1950, 44th of the 99 counties in Iowa with a tornado on record, an average of one every 1.9 years. They have killed 7 people and injured 100. 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
39
Deaths
7
Injuries
100
F4 and above
1
Worst on record
F4, May 24, 1989

The deadliest in Marshall County

  1. F3, Marshall, Jasper and Poweshiek counties, IowaSeptember 16, 19786 killed, 45 injured
  2. F3, Marshall, Tama, Benton and Linn counties, IowaApril 23, 19611 killed, 12 injured

The strongest

  1. F4, Hamilton, Story, Hardin and Marshall counties, IowaMay 24, 1989F4, 66.0 mi (106 km)
  2. F3, Marshall, Tama, Benton and Linn counties, IowaApril 23, 1961F3, 87.7 mi (141 km)
  3. F3, Marshall, Jasper and Poweshiek counties, IowaSeptember 16, 1978F3, 31.8 mi (51 km)
  4. EF3, Marshall County, IowaJuly 19, 2018EF3, 8.4 mi (14 km)
  5. F3, Marshall County, IowaJune 1, 1951F3, 1.5 mi (2 km)
  6. F2, Marshall County, IowaApril 10, 1981F2, 5.6 mi (9 km)
  7. F2, Marshall County, IowaJune 11, 1969F2, 1.0 mi (2 km)
  8. F2, Marshall County, IowaJune 6, 1969F2, 0.1 mi (0 km)
  9. F2, Marshall County, IowaMay 28, 1962F2, 0.1 mi (0 km)

Every year with a tornado

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

YearTornadoesDeathsInjuriesStrongest
20204EF1
2018222EF3
20151EF0
20142EF1
20082EF1
20046F1
20011F1
20001F1
19982F1
19961F0
19941F1
19931F0
19911F1
19892F4
19871F0
198119F2
19781645F3
19741F0
19694F2
19661F1
196215F2
19611112F3
195117F3

Every tornado that crossed Marshall County

39 tornadoes, newest first.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 10, 202011:39 AM CDTEF1Marshall2.9100$20,000
August 10, 202011:36 AM CDTUnratedMarshall0.450
August 10, 202011:30 AM CDTUnratedMarshall1.050
March 28, 20204:26 PM CDTEF0Marshall1.375
July 19, 20184:24 PM CDTEF3Marshall8.41,20022$200 million
July 19, 20184:11 PM CDTEF0Marshall0.840
November 11, 20154:15 PM CSTEF0Marshall1.9100$1,000
June 30, 20141:15 PM CDTEF0Marshall6.5150$52,000
June 30, 20141:02 PM CDTEF1Story12.0460$220,000
July 19, 20088:10 PM CDTEF0Marshall0.725
June 8, 20084:10 PM CDTEF1Marshall1.075$30,000
September 5, 20049:17 PM CDTF1Marshall3.530$10,000
September 5, 20049:17 PM CDTF0Marshall3.025$20,000
August 26, 20048:40 PM CDTF1Marshall3.030$50,000
August 3, 20045:20 PM CDTF1Marshall5.0100$100,000
May 22, 20048:40 PM CDTF1Marshall17.0100$10,000
May 22, 20048:19 PM CDTF0Marshall0.540
April 11, 20013:40 PM CDTF1Jasper17.545$10,000
June 13, 20006:44 PM CDTF1Marshall14.040$150,000
June 29, 19981:50 PM CDTF1Marshall1.050$20,000
May 30, 19981:56 PM CDTF1Story22.050$10,000
May 19, 19966:30 PM CDTF0Marshall0.125
April 14, 199411:21 PM CDTF1Marshall1.530$50,000 to $500,000
July 18, 199312:38 PM CDTF0Marshall0.120$50 to $500
September 12, 19913:30 PM CDTF1Marshall0.620$5,000 to $50,000
May 24, 19898:40 PM CDTF0Marshall0.250$500 to $5,000
May 24, 19896:20 PM CDTF4Hamilton66.0150$5 million to $50 million
July 11, 198711:46 PM CDTF0Marshall0.313$500 to $5,000
April 10, 19815:55 PM CSTF2Marshall5.65009$500,000 to $5 million
September 16, 19788:25 PM CDTF3Marshall31.8200645
June 18, 19749:01 PM CDTF0Marshall0.110$500 to $5,000
June 22, 19695:25 PM GMT-5F0Marshall1.0200$5,000 to $50,000
June 11, 19699:15 PM GMT-5F2Marshall1.0100$5,000 to $50,000
June 6, 196911:50 PM GMT-5F1Marshall0.1100$5,000 to $50,000
June 6, 19697:30 PM GMT-5F2Marshall0.1200$5,000 to $50,000
June 11, 19668:45 PM GMT-5F1Marshall0.150
May 28, 196210:00 PM GMT-5F2Marshall0.12005$50,000 to $500,000
April 23, 196110:15 AM GMT-6F3Marshall87.7800112$500,000 to $5 million
June 1, 195110:15 PM GMT-5F3Marshall1.58807

Nearby

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