Colorado lightning risk

64 counties scored 10 rated Very High

Jefferson County has the highest lightning risk in Colorado, scoring 99.7 out of 100 — rated "Very High" by FEMA's National Risk Index. Recorded lightning events across Colorado have decreased 78% over the past five years compared to the prior five-year period.

# County NRI score Rating NOAA events
2016–2026
1 Jefferson County 99.7 Very High 2
2 Douglas County 99.3 Very High 3
3 Larimer County 99.2 Very High 3
4 Boulder County 99 Very High 1
5 Pueblo County 99 Very High 0
6 El Paso County 98.9 Very High 2
7 Denver County 98.6 Very High 1
8 Arapahoe County 98.4 Very High 1
9 Mesa County 97.3 Very High 1
10 Adams County 96.7 Very High 0
11 Fremont County 96 Relatively High 1
12 Otero County 92 Relatively High 0
13 Weld County 91.6 Relatively High 1
14 Eagle County 89.4 Relatively High 0
15 Montrose County 87.5 Relatively High 1
16 Montezuma County 86.6 Relatively High 1
17 Chaffee County 86.4 Relatively High 0
18 Broomfield County 86.2 Relatively High 1
19 Prowers County 85.8 Relatively High 0
20 La Plata County 85.2 Relatively High 1
21 Rio Grande County 83.7 Relatively High 0
22 Teller County 83.1 Relatively High 0
23 Delta County 83 Relatively High 0
24 Garfield County 82.1 Relatively High 0
25 Grand County 81.8 Relatively Moderate 0
26 Rio Blanco County 81.8 Relatively Moderate 0
27 Summit County 80.8 Relatively Moderate 0
28 Custer County 79.3 Relatively Moderate 0
29 Dolores County 76.3 Relatively Moderate 1
30 Saguache County 76.2 Relatively Moderate 0
31 Park County 67.9 Relatively Moderate 1
32 Clear Creek County 67.8 Relatively Moderate 0
33 Las Animas County 67.6 Relatively Moderate 0
34 Pitkin County 66.5 Relatively Moderate 0
35 Routt County 65.6 Relatively Moderate 0
36 Alamosa County 65.4 Relatively Moderate 0
37 Huerfano County 62.3 Relatively Moderate 0
38 Gunnison County 62.1 Relatively Moderate 1
39 Ouray County 61.1 Relatively Moderate 0
40 Mineral County 60.8 Relatively Moderate 0
41 Archuleta County 60.6 Relatively Moderate 2
42 Baca County 58.5 Relatively Moderate 0
43 San Miguel County 56 Relatively Low 0
44 Logan County 55.2 Relatively Low 0
45 Crowley County 42.7 Relatively Low 0
46 Elbert County 42.5 Relatively Low 1
47 Gilpin County 42 Relatively Low 0
48 Conejos County 39.8 Relatively Low 0
49 Lake County 38.4 Relatively Low 0
50 San Juan County 36.4 Relatively Low 0
51 Costilla County 33.6 Relatively Low 0
52 Bent County 30.8 Relatively Low 0
53 Moffat County 29.7 Relatively Low 0
54 Morgan County 28.3 Relatively Low 1
55 Yuma County 25.7 Relatively Low 0
56 Sedgwick County 24 Relatively Low 0
57 Kit Carson County 23.9 Very Low 0
58 Phillips County 21.4 Very Low 0
59 Hinsdale County 19.3 Very Low 0
60 Lincoln County 17 Very Low 0
61 Jackson County 14.1 Very Low 1
62 Kiowa County 9 Very Low 0
63 Washington County 8.7 Very Low 0
64 Cheyenne County 7.4 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 Colorado:

Frequently asked questions

What is the highest lightning risk county in Colorado?

Jefferson County, CO has the highest lightning risk in Colorado, with a FEMA National Risk Index score of 99.7 out of 100 (rated "Very High").

How many counties in Colorado are rated Very High for lightning risk?

10 of 64 scored Colorado counties are rated "Very High" for lightning risk by FEMA's National Risk Index.

What causes lightning risk in Colorado?

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.