North Dakota tornado risk
Cass County has the highest tornado risk in North Dakota, scoring 89.7 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index. Recorded tornado events across North Dakota have increased 16% over the past five years compared to the prior five-year period.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | Cass County | 89.7 | Relatively Moderate | 15 |
| 2 | Burleigh County | 83 | Relatively Moderate | 12 |
| 3 | Ward County | 66.1 | Relatively Moderate | 0 |
| 4 | Grand Forks County | 60.7 | Relatively Low | 31 |
| 5 | Morton County | 57.3 | Relatively Low | 8 |
| 6 | Williams County | 53.1 | Relatively Low | 2 |
| 7 | Richland County | 49.6 | Relatively Low | 9 |
| 8 | Stark County | 47.9 | Relatively Low | 3 |
| 9 | Stutsman County | 47.1 | Relatively Low | 8 |
| 10 | McLean County | 45.5 | Relatively Low | 9 |
| 11 | Barnes County | 41.8 | Relatively Low | 10 |
| 12 | Emmons County | 40.5 | Relatively Low | 5 |
| 13 | Walsh County | 40.3 | Relatively Low | 7 |
| 14 | McKenzie County | 33.1 | Relatively Low | 7 |
| 15 | Mountrail County | 32.5 | Relatively Low | 3 |
| 16 | Rolette County | 31.1 | Relatively Low | 3 |
| 17 | Traill County | 30 | Relatively Low | 8 |
| 18 | Mercer County | 28.5 | Relatively Low | 3 |
| 19 | McHenry County | 27.6 | Relatively Low | 7 |
| 20 | Ramsey County | 27.2 | Relatively Low | 7 |
| 21 | Bottineau County | 26 | Very Low | 4 |
| 22 | McIntosh County | 25.6 | Very Low | 2 |
| 23 | Hettinger County | 25.4 | Very Low | 2 |
| 24 | Sioux County | 25 | Very Low | 1 |
| 25 | Dickey County | 24.8 | Very Low | 2 |
| 26 | Ransom County | 24.1 | Very Low | 6 |
| 27 | Dunn County | 24 | Very Low | 6 |
| 28 | Wells County | 22.7 | Very Low | 3 |
| 29 | Sheridan County | 22.4 | Very Low | 6 |
| 30 | Nelson County | 21.5 | Very Low | 10 |
| 31 | Pembina County | 21.3 | Very Low | 3 |
| 32 | Benson County | 20.9 | Very Low | 6 |
| 33 | Divide County | 20 | Very Low | 0 |
| 34 | LaMoure County | 20 | Very Low | 8 |
| 35 | Foster County | 18.3 | Very Low | 4 |
| 36 | Logan County | 18.1 | Very Low | 1 |
| 37 | Grant County | 17.4 | Very Low | 1 |
| 38 | Kidder County | 17 | Very Low | 4 |
| 39 | Cavalier County | 16.9 | Very Low | 9 |
| 40 | Sargent County | 16.9 | Very Low | 2 |
| 41 | Steele County | 16.8 | Very Low | 6 |
| 42 | Griggs County | 16.3 | Very Low | 5 |
| 43 | Pierce County | 15.6 | Very Low | 0 |
| 44 | Eddy County | 14.2 | Very Low | 3 |
| 45 | Golden Valley County | 13.2 | Very Low | 1 |
| 46 | Adams County | 12.3 | Very Low | 2 |
| 47 | Oliver County | 11.7 | Very Low | 3 |
| 48 | Bowman County | 11.5 | Very Low | 0 |
| 49 | Renville County | 10.5 | Very Low | 1 |
| 50 | Burke County | 9.5 | Very Low | 0 |
| 51 | Billings County | 8.5 | Very Low | 0 |
| 52 | Towner County | 7.8 | Very Low | 8 |
| 53 | Slope County | 5.5 | Very Low | 0 |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.
Tornado risk nationally:
Other hazard risks in North Dakota:
Frequently asked questions
What is the highest tornado risk county in North Dakota?
Cass County, ND has the highest tornado risk in North Dakota, with a FEMA National Risk Index score of 89.7 out of 100 (rated "Relatively Moderate").
What causes tornado risk in North Dakota?
Tornado risk concentrates in the central and southern plains ("Tornado Alley") and the Southeast ("Dixie Alley"), where atmospheric conditions favor supercell thunderstorm development. The highest scores often belong to counties with significant mobile home and manufactured housing stock, which carries disproportionate tornado mortality risk.