Alaska tsunami risk
Aleutians West Census Area has the highest tsunami risk in Alaska, scoring 87.7 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Aleutians West Census Area | 87.7 | Relatively Moderate |
| 2 | Kenai Peninsula Borough | 81.5 | Relatively Moderate |
| 3 | Kodiak Island Borough | 80 | Relatively Moderate |
| 4 | Aleutians East Borough | 66.2 | Relatively Low |
| 5 | Sitka City and Borough | 55.4 | Relatively Low |
| 6 | Anchorage Municipality | 53.8 | Relatively Low |
| 7 | Lake and Peninsula Borough | 50.8 | Relatively Low |
| 8 | Ketchikan Gateway Borough | 36.9 | Very Low |
| 9 | Prince of Wales-Hyder Census Area | 33.8 | Very Low |
| 10 | Juneau City and Borough | 27.7 | Very Low |
| 11 | Chugach Census Area | 24.6 | Very Low |
| 12 | Hoonah-Angoon Census Area | 21.5 | Very Low |
| 13 | Haines Borough | 20 | Very Low |
| 14 | Bethel Census Area | 16.9 | Very Low |
| 15 | Yakutat City and Borough | 12.3 | Very Low |
| 16 | Matanuska-Susitna Borough | 9.2 | Very Low |
| 17 | Skagway Municipality | 4.6 | Very Low |
| 18 | Dillingham Census Area | 1.5 | 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 Alaska:
Frequently asked questions
What is the highest tsunami risk county in Alaska?
Aleutians West Census Area, AK has the highest tsunami risk in Alaska, with a FEMA National Risk Index score of 87.7 out of 100 (rated "Relatively Moderate").
What causes tsunami risk in Alaska?
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.