Arizona avalanche risk

14 counties scored 0 rated Very High

Coconino County has the highest avalanche risk in Arizona, scoring 81.7 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.

# County NRI score Rating
1 Coconino County 81.7 Relatively Moderate
2 Mohave County 68.6 Relatively Low
3 Gila County 58 Very Low
4 Graham County 54.4 Very Low
5 Cochise County 54.2 Very Low
6 Yavapai County 53.8 Very Low
7 Navajo County 50.9 Very Low
8 Apache County 50.7 Very Low
9 Pima County 46.3 Very Low
10 Greenlee County 43.6 Very Low
11 Maricopa County 32.9 Very Low
12 Santa Cruz County 31 Very Low
13 Pinal County 26.2 Very Low
14 La Paz County 13.9 Very Low

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.

Avalanche risk nationally:

Other hazard risks in Arizona:

Frequently asked questions

What is the highest avalanche risk county in Arizona?

Coconino County, AZ has the highest avalanche risk in Arizona, with a FEMA National Risk Index score of 81.7 out of 100 (rated "Relatively Moderate").

What causes avalanche risk in Arizona?

Avalanche risk reflects expected annual losses from snow avalanche events, primarily affecting mountain counties in the West. The highest scores belong to Colorado, Utah, Montana, and Washington counties where active ski terrain, mountain highways, and communities overlap with historically active avalanche paths and high seasonal snowpack. Avalanche events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.