Utah heat wave risk
Utah County has the highest heat wave risk in Utah, scoring 94.3 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index. NOAA has recorded 21 heat wave events across Utah over the past decade.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | Utah County | 94.3 | Relatively Moderate | 3 |
| 2 | Salt Lake County | 92.9 | Relatively Moderate | 2 |
| 3 | Washington County | 90.8 | Relatively Moderate | 0 |
| 4 | Kane County | 86.6 | Relatively Moderate | 1 |
| 5 | Davis County | 86.3 | Relatively Moderate | 2 |
| 6 | Garfield County | 82.5 | Relatively Moderate | 1 |
| 7 | Weber County | 81.4 | Relatively Moderate | 0 |
| 8 | San Juan County | 78.2 | Relatively Low | 0 |
| 9 | Cache County | 56.2 | Relatively Low | 0 |
| 10 | Tooele County | 53.9 | Relatively Low | 2 |
| 11 | Sanpete County | 45.3 | Relatively Low | 0 |
| 12 | Iron County | 44.4 | Relatively Low | 0 |
| 13 | Box Elder County | 43.8 | Relatively Low | 2 |
| 14 | Wayne County | 39.6 | Relatively Low | 1 |
| 15 | Millard County | 37.4 | Very Low | 0 |
| 16 | Juab County | 37.3 | Very Low | 0 |
| 17 | Grand County | 32.3 | Very Low | 4 |
| 18 | Emery County | 32.1 | Very Low | 1 |
| 19 | Beaver County | 32 | Very Low | 0 |
| 20 | Sevier County | 27.8 | Very Low | 0 |
| 21 | Uintah County | 26.5 | Very Low | 1 |
| 22 | Carbon County | 26.1 | Very Low | 0 |
| 23 | Duchesne County | 21 | Very Low | 1 |
| 24 | Wasatch County | 17.1 | Very Low | 0 |
| 25 | Summit County | 14 | Very Low | 0 |
| 26 | Piute County | 9.1 | Very Low | 0 |
| 27 | Morgan County | 7.9 | Very Low | 0 |
| 28 | Rich County | 1.8 | Very Low | 0 |
| 29 | Daggett County | 0 | No Rating | 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.
Heat Wave risk nationally:
Other hazard risks in Utah:
Frequently asked questions
What is the highest heat wave risk county in Utah?
Utah County, UT has the highest heat wave risk in Utah, with a FEMA National Risk Index score of 94.3 out of 100 (rated "Relatively Moderate").
What causes heat wave risk in Utah?
Heat is consistently the leading cause of weather-related mortality in the US, yet it remains underrepresented in federal disaster declarations relative to its actual impact. High scores reflect a combination of extreme temperature exposure, population vulnerability (elderly, outdoor workers), and limited access to cooling infrastructure.