Ohio tornado risk

88 counties scored 2 rated Very High

Hamilton County has the highest tornado risk in Ohio, scoring 99.4 out of 100 — rated "Very High" by FEMA's National Risk Index. Recorded tornado events across Ohio have increased 47% over the past five years compared to the prior five-year period.

# County NRI score Rating NOAA events
2016–2026
1 Hamilton County 99.4 Very High 4
2 Cuyahoga County 99 Very High 6
3 Franklin County 98.4 Relatively High 9
4 Butler County 98 Relatively High 9
5 Lucas County 97.3 Relatively High 3
6 Montgomery County 92.6 Relatively High 10
7 Mahoning County 91.2 Relatively High 1
8 Summit County 91.1 Relatively High 5
9 Lorain County 90.9 Relatively High 7
10 Trumbull County 90.8 Relatively High 9
11 Stark County 87.7 Relatively Moderate 6
12 Medina County 84.6 Relatively Moderate 5
13 Clermont County 83.6 Relatively Moderate 8
14 Warren County 83.4 Relatively Moderate 13
15 Clark County 82.3 Relatively Moderate 15
16 Darke County 81.8 Relatively Moderate 13
17 Delaware County 81.5 Relatively Moderate 6
18 Greene County 81.3 Relatively Moderate 8
19 Wood County 80.5 Relatively Moderate 1
20 Ashtabula County 78.8 Relatively Moderate 1
21 Erie County 77.9 Relatively Moderate 2
22 Preble County 76.7 Relatively Moderate 6
23 Wayne County 76.1 Relatively Moderate 3
24 Miami County 75.4 Relatively Moderate 17
25 Lake County 75.2 Relatively Moderate 3
26 Williams County 74.4 Relatively Moderate 0
27 Allen County 74.3 Relatively Moderate 4
28 Ottawa County 72.8 Relatively Moderate 4
29 Fairfield County 71.6 Relatively Moderate 4
30 Sandusky County 71.4 Relatively Moderate 6
31 Portage County 70.5 Relatively Moderate 4
32 Columbiana County 70 Relatively Moderate 5
33 Shelby County 68.5 Relatively Moderate 4
34 Hancock County 67.3 Relatively Moderate 3
35 Huron County 67.3 Relatively Moderate 14
36 Mercer County 67 Relatively Moderate 11
37 Fulton County 66.9 Relatively Moderate 1
38 Holmes County 66.7 Relatively Moderate 3
39 Knox County 64.3 Relatively Low 3
40 Defiance County 63.7 Relatively Low 4
41 Marion County 62.9 Relatively Low 2
42 Richland County 62.3 Relatively Low 4
43 Licking County 61.5 Relatively Low 6
44 Logan County 61.2 Relatively Low 2
45 Geauga County 59.6 Relatively Low 8
46 Auglaize County 58 Relatively Low 11
47 Seneca County 58 Relatively Low 3
48 Brown County 57.5 Relatively Low 10
49 Ashland County 57.3 Relatively Low 4
50 Muskingum County 56.3 Relatively Low 9
51 Ross County 56.3 Relatively Low 5
52 Highland County 56.2 Relatively Low 9
53 Belmont County 55.5 Relatively Low 3
54 Clinton County 55.5 Relatively Low 7
55 Pickaway County 52.9 Relatively Low 7
56 Paulding County 51.2 Relatively Low 5
57 Jefferson County 50.2 Relatively Low 4
58 Union County 49.5 Relatively Low 2
59 Henry County 48.5 Relatively Low 4
60 Putnam County 48.5 Relatively Low 6
61 Lawrence County 48.3 Relatively Low 4
62 Van Wert County 48.2 Relatively Low 11
63 Coshocton County 46.8 Relatively Low 1
64 Tuscarawas County 46.6 Relatively Low 2
65 Champaign County 46.4 Relatively Low 3
66 Scioto County 45 Relatively Low 0
67 Madison County 43.9 Relatively Low 6
68 Fayette County 43.3 Relatively Low 5
69 Crawford County 42 Relatively Low 7
70 Adams County 41.2 Relatively Low 2
71 Morrow County 40.6 Relatively Low 3
72 Wyandot County 40.5 Relatively Low 0
73 Athens County 37.4 Relatively Low 2
74 Pike County 37.4 Relatively Low 4
75 Guernsey County 36.8 Relatively Low 2
76 Hardin County 36.3 Relatively Low 4
77 Jackson County 33.9 Relatively Low 3
78 Hocking County 33.8 Relatively Low 3
79 Washington County 33.1 Relatively Low 1
80 Perry County 32.4 Relatively Low 2
81 Carroll County 28 Relatively Low 3
82 Gallia County 26.1 Very Low 1
83 Meigs County 25.5 Very Low 2
84 Noble County 24.7 Very Low 0
85 Monroe County 23.9 Very Low 1
86 Vinton County 21.3 Very Low 6
87 Harrison County 18.2 Very Low 1
88 Morgan County 17 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 Ohio:

Frequently asked questions

What is the highest tornado risk county in Ohio?

Hamilton County, OH has the highest tornado risk in Ohio, with a FEMA National Risk Index score of 99.4 out of 100 (rated "Very High").

How many counties in Ohio are rated Very High for tornado risk?

2 of 88 scored Ohio counties are rated "Very High" for tornado risk by FEMA's National Risk Index.

What causes tornado risk in Ohio?

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.