Arizona cold wave risk

15 counties scored 0 rated Very High

Coconino County has the highest cold wave risk in Arizona, scoring 80.2 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.

# County NRI score Rating
1 Coconino County 80.2 Relatively Moderate
2 Navajo County 73 Relatively Moderate
3 Apache County 62.7 Relatively Low
4 Cochise County 5 Very Low
5 Graham County 3.7 Very Low
6 Greenlee County 3.7 Very Low
7 Pinal County 3.4 Very Low
8 Pima County 3.1 Very Low
9 Gila County 3 Very Low
10 Yavapai County 2.8 Very Low
11 Mohave County 2.6 Very Low
12 La Paz County 0 No Rating
13 Maricopa County 0 No Rating
14 Santa Cruz County 0 No Rating
15 Yuma County 0 No Rating

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.

Cold Wave risk nationally:

Other hazard risks in Arizona:

Frequently asked questions

What is the highest cold wave risk county in Arizona?

Coconino County, AZ has the highest cold wave risk in Arizona, with a FEMA National Risk Index score of 80.2 out of 100 (rated "Relatively Moderate").

What causes cold wave risk in Arizona?

Cold wave risk captures expected losses from extended periods of extreme cold, including wind chill. The northern Plains, Great Lakes, and interior New England see the most severe and frequent cold events. Cold extremes cause significant excess mortality, especially among unhoused populations, the elderly, and those with inadequate heating or insulation. Cold and wind chill events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.