Montana recorded 444 tornadoes from 1950 through 2024, an average of 6 a year, in NOAA’s Storm Prediction Center database. They killed 4 people. The busiest year was 1991, with 30.
Tornadoes per 1,000 square miles since 1950: none under 10 10 to 25 25 to 50 50 to 75 75 to 100 over 100. Tap a county for its history.
Tornadoes by year
The rise since the 1990s is mostly better detection of weak tornadoes, not a jump in strong ones.
Tornado season in Montana
June is the peak, with 165 tornadoes since 1950 (37% of the total).
How strong
| Rating | Estimated 3-second gust | Tornadoes |
|---|---|---|
| F0 / EF0 | Light damage: 65 to 85 mph (EF scale) | 287 |
| F1 / EF1 | Moderate: 86 to 110 mph | 95 |
| F2 / EF2 | Considerable: 111 to 135 mph | 45 |
| F3 / EF3 | Severe: 136 to 165 mph | 10 |
| F4 / EF4 | Devastating: 166 to 200 mph | 1 |
| F5 / EF5 | Incredible: over 200 mph | 0 |
| EF-U | Unknown: no damage to rate (mostly since 2016) | 6 |
The deadliest tornadoes in Montana
| Date | Rating | Deaths in Montana | Counties |
|---|---|---|---|
| July 26, 2010 | EF3 | 2 | Sheridan County |
| July 19, 1952 | F3 | 1 | Wibaux County |
| July 9, 1983 | F1 | 1 | McCone County |
Counties with the most tornadoes
| County | Tornadoes since 1950 | Per 1,000 sq mi | Strongest |
|---|---|---|---|
| Valley County | 44 | 9 | EF2 |
| Fergus County | 28 | 6 | F2 |
| Yellowstone County | 21 | 8 | F3 |
| Powder River County | 18 | 5 | EF2 |
| Carter County | 18 | 5 | EF3 |
| Judith Basin County | 18 | 10 | F2 |
| Roosevelt County | 17 | 7 | EF2 |
| Chouteau County | 17 | 4 | F3 |
| Fallon County | 15 | 9 | EF3 |
| Dawson County | 15 | 6 | F4 |
| Phillips County | 15 | 3 | EF1 |
| Beaverhead County | 14 | 3 | F2 |
| Cascade County | 13 | 5 | F2 |
| Richland County | 13 | 6 | F2 |
| Garfield County | 12 | 2 | EF0 |
Big counties collect more tornadoes simply because they are big. By area, the most tornado-dense counties are Judith Basin County (10 per 1,000 sq mi), Fallon County (9 per 1,000 sq mi), Wibaux County (9 per 1,000 sq mi), Valley County (9 per 1,000 sq mi), Yellowstone County (8 per 1,000 sq mi).
Every county in Montana
Staying safe
When a tornado warning is issued, act at once. Go to a basement, storm shelter or safe room. With none, use a small windowless room on the lowest floor, as far from outside walls as you can, and cover your head and neck. Mobile homes and cars are not safe places to ride out a tornado: leave early for a sturdy building or shelter. Read the full tornado safety guide and the National Weather Service advice linked below.
Sources
- NOAA Storm Prediction Center: Severe Weather Database, tornadoes 1950 to 2024 (public domain)
- NOAA Storm Prediction Center: The Enhanced Fujita Scale (EF scale)
- National Weather Service: Tornado safety
Sources last checked 1 November 2026.
Frequently asked questions
How many tornadoes does Montana get a year?
About 6 on average from 1950 to 2024; recent years run higher because weak tornadoes are better detected.
When is tornado season in Montana?
June has had the most. Spring and early summer bring most of them.
What was the deadliest tornado in Montana?
July 26, 2010: 2 deaths in Montana.