Washington tsunami risk
Grays Harbor County has the highest tsunami risk in Washington, scoring 100 out of 100 — rated "Very High" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Grays Harbor County | 100 | Very High |
| 2 | Pacific County | 95.4 | Very High |
| 3 | Clallam County | 83.1 | Relatively Moderate |
| 4 | King County | 67.7 | Relatively Low |
| 5 | Kitsap County | 61.5 | Relatively Low |
| 6 | Wahkiakum County | 58.5 | Relatively Low |
| 7 | Pierce County | 49.2 | Relatively Low |
| 8 | Mason County | 43.1 | Very Low |
| 9 | Jefferson County | 40 | Very Low |
| 10 | Island County | 35.4 | Very Low |
| 11 | Skagit County | 30.8 | Very Low |
| 12 | Whatcom County | 23.1 | Very Low |
| 13 | Thurston County | 13.8 | Very Low |
| 14 | Snohomish County | 7.7 | Very Low |
| 15 | San Juan County | 6.2 | 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.
Tsunami risk nationally:
Other hazard risks in Washington:
Frequently asked questions
What is the highest tsunami risk county in Washington?
Grays Harbor County, WA has the highest tsunami risk in Washington, with a FEMA National Risk Index score of 100 out of 100 (rated "Very High").
How many counties in Washington are rated Very High for tsunami risk?
2 of 15 scored Washington counties are rated "Very High" for tsunami risk by FEMA's National Risk Index.
What causes tsunami risk in Washington?
Tsunami risk covers expected losses from seismically generated ocean waves. Risk concentrates on the Pacific Coast — especially Oregon, Washington, and Alaska — where the Cascadia Subduction Zone and other fault systems can generate destructive local tsunamis with little warning. Atlantic and Gulf coasts carry lower but non-zero risk from distant earthquake sources.