Arizona ice storm risk
Mohave County has the highest ice storm risk in Arizona, scoring 68.7 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Mohave County | 68.7 | Relatively Moderate |
| 2 | Navajo County | 63.3 | Relatively Moderate |
| 3 | Coconino County | 57.6 | Relatively Low |
| 4 | Apache County | 53.9 | Relatively 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.
Ice Storm risk nationally:
Other hazard risks in Arizona:
Frequently asked questions
What is the highest ice storm risk county in Arizona?
Mohave County, AZ has the highest ice storm risk in Arizona, with a FEMA National Risk Index score of 68.7 out of 100 (rated "Relatively Moderate").
What causes ice storm risk in Arizona?
Ice storm risk covers damaging freezing rain and sleet accumulation, which collapses power lines, trees, and structures. The highest-risk counties cluster in a band from eastern Texas and Arkansas through the Carolinas and New England, where warm Gulf moisture overruns cold arctic air most frequently. Ice storms cause catastrophic and long-lasting power outages. Ice storm and sleet events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.