Idaho lightning risk

44 counties scored 0 rated Very High

Ada County has the highest lightning risk in Idaho, scoring 90.1 out of 100 — rated "Relatively High" by FEMA's National Risk Index.

# County NRI score Rating NOAA events
2016–2026
1 Ada County 90.1 Relatively High 0
2 Bonneville County 89.5 Relatively High 6
3 Madison County 88.3 Relatively High 1
4 Canyon County 84.9 Relatively High 0
5 Bannock County 80 Relatively Moderate 3
6 Lemhi County 78.3 Relatively Moderate 0
7 Bingham County 74.4 Relatively Moderate 1
8 Cassia County 69.1 Relatively Moderate 0
9 Teton County 69.1 Relatively Moderate 1
10 Fremont County 68 Relatively Moderate 2
11 Jefferson County 54.7 Relatively Low 1
12 Twin Falls County 54.3 Relatively Low 0
13 Blaine County 53.9 Relatively Low 1
14 Minidoka County 51.7 Relatively Low 0
15 Bonner County 46.9 Relatively Low 0
16 Custer County 43.7 Relatively Low 0
17 Franklin County 39.2 Relatively Low 0
18 Caribou County 39 Relatively Low 0
19 Idaho County 33.2 Relatively Low 0
20 Jerome County 28.1 Relatively Low 0
21 Valley County 27 Relatively Low 0
22 Bear Lake County 26.8 Relatively Low 0
23 Kootenai County 24.5 Relatively Low 1
24 Elmore County 22 Very Low 0
25 Payette County 21.9 Very Low 0
26 Gooding County 21.5 Very Low 0
27 Power County 21.4 Very Low 0
28 Gem County 19.9 Very Low 0
29 Owyhee County 18.1 Very Low 0
30 Boundary County 17.9 Very Low 0
31 Washington County 17.5 Very Low 0
32 Oneida County 13.2 Very Low 0
33 Lincoln County 12.7 Very Low 0
34 Adams County 9.5 Very Low 0
35 Boise County 9.3 Very Low 0
36 Nez Perce County 8.9 Very Low 0
37 Latah County 6.2 Very Low 0
38 Shoshone County 5.9 Very Low 1
39 Butte County 4.8 Very Low 1
40 Clearwater County 4.6 Very Low 0
41 Benewah County 3.6 Very Low 0
42 Clark County 3.3 Very Low 0
43 Lewis County 2.2 Very Low 0
44 Camas County 1.7 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.

Lightning risk nationally:

Other hazard risks in Idaho:

Frequently asked questions

What is the highest lightning risk county in Idaho?

Ada County, ID has the highest lightning risk in Idaho, with a FEMA National Risk Index score of 90.1 out of 100 (rated "Relatively High").

What causes lightning risk in Idaho?

Lightning risk reflects expected annual losses from cloud-to-ground strikes, which ignite building fires, damage electrical systems, and cause fatalities. Florida consistently leads the US in lightning density. High scores also appear across the Gulf Coast, Southeast, and central Plains, where afternoon convective storms are most frequent in summer months.