South Dakota has a long and well-documented history of severe storms, with 1,918 confirmed tornadoes, 16,509 hailstorm events and 11,680 damaging-wind events recorded by the National Weather Service since 1950., and averages 25.6 tornadoes per year over the 75-year record. South Dakota lies within Tornado Alley, the historic core of the country’s most active severe-weather climate. The interactive map below plots every significant severe-weather event in South Dakota from the official NOAA Storm Events Database (1950 through September 2025).
Use the map to find your county, click any marker for the date, magnitude, and casualty details of that event, and switch between tornadoes, hail and wind using the chips. For the national view across all 50 states, see our NOAA Storm Reports interactive map. For tornado tracks specifically, see the US Tornado Tracks map; for hail size and frequency, the US Hailstorms map.
South Dakota Severe Weather by the Numbers (1950–2025)
- 1,918 tornadoes recorded between 1950 and 2025
- 320 violent tornadoes rated F2/EF2 or stronger
- 1 confirmed F5/EF5 tornado on record — the maximum rating on the Fujita and Enhanced Fujita scales
- 19 direct tornado deaths and 478 direct injuries
- 16,509 hailstorm events recorded by the NWS
- 11,680 damaging-wind events on record
- 25.6 tornadoes per year on average across the 75-year record
- June is the peak severe-weather month, accounting for roughly 39% of South Dakota tornadoes
- 84 total direct deaths from all severe-weather event types tracked by the NWS
When South Dakota Severe Weather Happens
South Dakota tornado activity is heavily concentrated in spring. March, April, May and June account for 66% of all South Dakota tornadoes, with June alone responsible for roughly 39%.
- June: 748 tornadoes (39%) — peak month
- May: 452 tornadoes (23.6%)
- July: 381 tornadoes (19.9%)
- August: 190 tornadoes (9.9%)
- September: 61 tornadoes (3.2%)
- April: 58 tornadoes (3%)
Top 10 South Dakota Counties by Tornado Frequency
Tornado activity in South Dakota is geographically broad, but a handful of counties have logged many times the state average. The combination of population density (more spotters and damage reports), county land area and local climatology drives the rankings below.
| County | Tornadoes since 1950 |
|---|---|
| Brown | 84 |
| Lincoln | 58 |
| Pennington | 49 |
| Kingsbury | 47 |
| Meade | 46 |
| Minnehaha | 46 |
| Charles Mix | 45 |
| Hutchinson | 45 |
| Perkins | 45 |
| Turner | 44 |
The Deadliest Tornadoes in South Dakota History
South Dakota has lost 19 lives to tornadoes since the National Weather Service began systematic tornado record-keeping in 1950. The single deadliest event killed 6 people in McCook County in 1998, rated F4 on the Fujita scale.
| Date | Location | Rating | Direct deaths | Direct injuries |
|---|---|---|---|---|
| May 30, 1998 | McCook County (near Spencer) | F4 | 6 | 150 |
| July 31, 1966 | McPherson County | F3 | 2 | 4 |
| June 20, 1957 | Spink County | F2 | 1 | 0 |
| June 21, 1961 | Clark County | F3 | 1 | 7 |
| June 7, 1965 | Lincoln County | — | 1 | 0 |
| June 7, 1965 | Turner County | F4 | 1 | 0 |
| July 31, 1966 | Brown County | F2 | 1 | 3 |
| July 14, 1970 | Lincoln County | F2 | 1 | 1 |
| June 24, 1973 | Charles Mix County | F2 | 1 | 1 |
| July 1, 1973 | Brown County | F3 | 1 | 3 |
South Dakota Tornado Strength Distribution
Most South Dakota tornadoes are weak: roughly 82% are rated F0/EF0 or F1/EF1. Violent tornadoes (F2+/EF2+) account for around 18.3% of rated tornadoes in the state. South Dakota is one of the few states with a confirmed F5 or EF5 tornado on record.
- F0/EF0 (weak): 1,040 tornadoes — 59.5% of rated events
- F1/EF1: 388 tornadoes — 22.2% of rated events
- F2/EF2 (strong): 248 tornadoes — 14.2% of rated events
- F3/EF3: 63 tornadoes — 3.6% of rated events
- F4/EF4 (violent): 8 tornadoes — 0.5% of rated events
- F5/EF5 (incredible): 1 tornadoes — 0.1% of rated events
Record-Setting Severe Weather in South Dakota
Largest hailstone: 8.00 inches in diameter, observed in Lyman County near Vivian on July 23, 2010. The three largest hailstones on record in South Dakota measured 8.00″, 6.88″, 6.13″.
Highest measured wind gust: 123 knots (142 mph) recorded in Dewey County near Lantry on June 16, 2010. Most damaging-wind events in South Dakota are estimated rather than measured because anemometers are sparse across the rural areas where supercells most often produce destructive thunderstorm winds.
How South Dakota Compares Nationally
South Dakota ranks 17th nationally for tornado frequency, in the middle of the pack of US states by severe-weather activity.
- Tornadoes (top 5): Texas (9,908), Kansas (4,890), Oklahoma (4,856), Florida (3,779), Iowa (3,417).
- South Dakota tornado total: 1,918 — ranked 17th nationally.
- South Dakota hail total: 16,509 hail events on record since 1950.
- South Dakota wind total: 11,680 damaging-wind events on record since 1950.
Frequently Asked Questions
How many tornadoes does South Dakota have on average per year?
South Dakota averages 25.6 tornadoes per year over the 1950–2025 period. Counts vary widely year to year, but the long-term mean over 75 years of NWS records is a reliable benchmark for typical activity.
What was the deadliest tornado in South Dakota history?
The May 30, 1998 tornado, rated F4 on the Fujita scale, killed 6 people and injured 150 in McCook County. It remains the single deadliest tornado in the South Dakota modern record.
Where in South Dakota are tornadoes most common?
The single county with the most tornadoes on record is Brown County with 84 events. The three most active counties overall are Brown, Lincoln, Pennington.
How does South Dakota compare to its neighbors?
South Dakota shares a severe-weather climate with North Dakota, Minnesota, Iowa, Nebraska, Wyoming, Montana. Severe storms regularly cross state lines, so the same supercells, hail cores and wind events often appear in South Dakota’s neighbors’ records on the same date.
How recent is the data on this map?
The map and statistics on this page are pulled from NOAA’s official Storm Events Database, which currently runs from January 1950 through September 2025. New records typically appear in the database within 30–90 days of the event date, once damage surveys and ratings are complete.
Compare South Dakota to Neighboring States
Severe weather doesn’t stop at state lines. The same supercell systems that produce South Dakota tornadoes regularly cross into neighboring states. Compare South Dakota’s storm history to its land neighbors:
- North Dakota severe storm history — ranked 19th nationally
- Minnesota severe storm history — ranked 14th nationally
- Iowa severe storm history — ranked 5th nationally, core Tornado Alley state
- Nebraska severe storm history — ranked 7th nationally, core Tornado Alley state
- Wyoming severe storm history — ranked 28th nationally, mountain-west severe weather, mostly hail and high wind
- Montana severe storm history — ranked 32nd nationally, mountain-west severe weather, mostly hail and high wind
Explore the national NOAA Storm Reports map · US Tornado Tracks map · US Hailstorms map
