Washington heat wave risk
King County has the highest heat wave risk in Washington, scoring 98.2 out of 100 — rated "Relatively High" by FEMA's National Risk Index. NOAA has recorded 53 heat wave events across Washington over the past decade.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | King County | 98.2 | Relatively High | 0 |
| 2 | Pierce County | 97.3 | Relatively High | 0 |
| 3 | Snohomish County | 96.9 | Relatively High | 0 |
| 4 | Clark County | 95.9 | Relatively Moderate | 0 |
| 5 | Spokane County | 94.9 | Relatively Moderate | 1 |
| 6 | Benton County | 94.4 | Relatively Moderate | 9 |
| 7 | Yakima County | 93.5 | Relatively Moderate | 5 |
| 8 | Cowlitz County | 91.4 | Relatively Moderate | 0 |
| 9 | Thurston County | 90.6 | Relatively Moderate | 0 |
| 10 | Kitsap County | 89.5 | Relatively Moderate | 0 |
| 11 | Franklin County | 87.7 | Relatively Moderate | 9 |
| 12 | Grant County | 87.1 | Relatively Moderate | 1 |
| 13 | Walla Walla County | 81.5 | Relatively Moderate | 6 |
| 14 | Whatcom County | 78.9 | Relatively Moderate | 0 |
| 15 | Lewis County | 77.9 | Relatively Low | 0 |
| 16 | Chelan County | 77.2 | Relatively Low | 1 |
| 17 | Okanogan County | 72.4 | Relatively Low | 0 |
| 18 | Skagit County | 68.9 | Relatively Low | 0 |
| 19 | Mason County | 68 | Relatively Low | 0 |
| 20 | Douglas County | 67.8 | Relatively Low | 1 |
| 21 | Kittitas County | 66.2 | Relatively Low | 3 |
| 22 | Stevens County | 62 | Relatively Low | 1 |
| 23 | Whitman County | 60.8 | Relatively Low | 2 |
| 24 | Grays Harbor County | 58.9 | Relatively Low | 0 |
| 25 | Asotin County | 53.8 | Relatively Low | 0 |
| 26 | Adams County | 51.9 | Relatively Low | 1 |
| 27 | Pacific County | 45.1 | Relatively Low | 0 |
| 28 | Clallam County | 42 | Relatively Low | 0 |
| 29 | Klickitat County | 40.6 | Relatively Low | 2 |
| 30 | Lincoln County | 40 | Relatively Low | 1 |
| 31 | Wahkiakum County | 39.9 | Relatively Low | 0 |
| 32 | Skamania County | 38.7 | Very Low | 0 |
| 33 | Jefferson County | 34.8 | Very Low | 0 |
| 34 | Pend Oreille County | 32.8 | Very Low | 1 |
| 35 | Ferry County | 30.6 | Very Low | 1 |
| 36 | Island County | 29.7 | Very Low | 0 |
| 37 | Columbia County | 25.6 | Very Low | 6 |
| 38 | Garfield County | 14.9 | Very Low | 0 |
| 39 | San Juan County | 13.9 | Very Low | 2 |
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 Washington:
Frequently asked questions
What is the highest heat wave risk county in Washington?
King County, WA has the highest heat wave risk in Washington, with a FEMA National Risk Index score of 98.2 out of 100 (rated "Relatively High").
What causes heat wave risk in Washington?
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.