Tornado History Map

Union County, South Dakota tornado history

29 tornadoes recorded in or across Union County from 1954 to 2014, coloured by rating on the map.

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Years1950 to 2025
Rating (F or EF scale)

Shows tornadoes that started in, or crossed, the chosen state. To see how many have passed near you, search a town or ZIP code, or tap the map.

Key
  • F0 / EF0 Light damage
  • F1 / EF1 Moderate damage
  • F2 / EF2 Considerable damage
  • F3 / EF3 Severe damage
  • F4 / EF4 Devastating damage
  • F5 / EF5 Incredible damage
  • Unknown Not rated (2007 onwards)

How to read the lines. Each line is one tornado, drawn from where it started to where it ended, coloured and sized by its rating. A dot means the record has no end point. Tap a line for its details, or tap anywhere else to see how many tornadoes have passed nearby. Weaker tornadoes appear as you zoom in. Ratings use the Fujita (F) scale before 1 February 2007 and the Enhanced Fujita (EF) scale from then on.

Tornadoes in Union County

The Storm Prediction Center records 29 tornadoes whose paths touched Union County, South Dakota between 1954 and 2014. None of them is recorded as having killed anyone. The busiest month is July, with 12 tornadoes. The strongest was an F3 on 7 June 1965. The most recent was on 11 May 2014.

  • 29tornadoes
  • 0deaths
  • 1injury
  • 629per 10,000 sq mi of land

A tornado that crossed several counties counts in each one, so county counts add up to more than the state's.

How strong were the tornadoes in Union County?

RatingTornadoesShare
F0 / EF01966%
F1 / EF1724%
F2 / EF227%
F3 / EF313%
F4 / EF400%
F5 / EF500%
Unknown rating00%

Union County tornadoes over time

Tornadoes by decade
Bar chart of tornadoes by period. The most is 8 in 1980s.1950s11960s41970s41980s81990s32000s62010s3

The 2010s only run to 2014, so that bar is for a shorter period. The record starts in 1950.

Show the numbers
PeriodCount
1950s1
1960s4
1970s4
1980s8
1990s3
2000s6
2010s3
Tornadoes by month
Bar chart of tornadoes by period. The most is 12 in Jul.Jan0Feb0Mar0Apr1May7Jun4Jul12Aug3Sep0Oct2Nov0Dec0
Show the numbers
PeriodCount
Jan0
Feb0
Mar0
Apr1
May7
Jun4
Jul12
Aug3
Sep0
Oct2
Nov0
Dec0

Records for Union County

  • Strongest: South Dakota tornado7 June 1965, F3, 0.1 miles long
  • Longest path: Iowa tornado5 July 1978, F2, 20.8 miles long
  • Most recent: South Dakota tornado11 May 2014, EF0, 2.4 miles long

Many of these tornadoes killed or injured people. The numbers are the official record's, and they may be revised.

More in South Dakota

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