Top counties by avalanche risk
Avalanche risk reflects expected annual losses from snow avalanche events, primarily affecting mountain counties in the West. The highest scores belong to Colorado, Utah, Montana, and Washington counties where active ski terrain, mountain highways, and communities overlap with historically active avalanche paths and high seasonal snowpack. Avalanche events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.
| # | County | State | NRI score | Rating |
|---|---|---|---|---|
| 1 | Teton County | WY | 100 | Very High |
| 2 | Matanuska-Susitna Borough | AK | 99.9 | Very High |
| 3 | Kenai Peninsula Borough | AK | 99.7 | Very High |
| 4 | Park County | MT | 99.6 | Very High |
| 5 | Copper River Census Area | AK | 99.4 | Very High |
| 6 | King County | WA | 99.3 | Very High |
| 7 | Salt Lake County | UT | 99.1 | Very High |
| 8 | Summit County | CO | 99 | Very High |
| 9 | Pitkin County | CO | 98.8 | Very High |
| 10 | Lincoln County | WY | 98.7 | Very High |
| 11 | Flathead County | MT | 98.5 | Very High |
| 12 | Pierce County | WA | 98.4 | Very High |
| 13 | Whatcom County | WA | 98.2 | Very High |
| 14 | Summit County | UT | 98.1 | Very High |
| 15 | Clear Creek County | CO | 98 | Very High |
| 16 | Placer County | CA | 97.8 | Very High |
| 17 | Kittitas County | WA | 97.7 | Very High |
| 18 | Coos County | NH | 97.5 | Very High |
| 19 | Madison County | MT | 97.4 | Very High |
| 20 | Denali Borough | AK | 97.2 | Very High |
| 21 | Anchorage Municipality | AK | 97.1 | Very High |
| 22 | Blaine County | ID | 96.9 | Very High |
| 23 | Custer County | ID | 96.8 | Very High |
| 24 | Gallatin County | MT | 96.6 | Very High |
| 25 | Inyo County | CA | 96.5 | Very High |
| 26 | Eagle County | CO | 96.3 | Very High |
| 27 | Gunnison County | CO | 96.2 | Very High |
| 28 | Shoshone County | ID | 96.1 | Very High |
| 29 | Jackson County | CO | 95.9 | Very High |
| 30 | San Juan County | CO | 95.8 | Very High |
| 31 | Hoonah-Angoon Census Area | AK | 95.6 | Very High |
| 32 | Sanpete County | UT | 95.5 | Very High |
| 33 | Chaffee County | CO | 95.3 | Very High |
| 34 | Chelan County | WA | 95.2 | Very High |
| 35 | Grand County | CO | 95 | Very High |
| 36 | Yakima County | WA | 94.9 | Very High |
| 37 | Chugach Census Area | AK | 94.7 | Very High |
| 38 | Bonner County | ID | 94.6 | Relatively High |
| 39 | Southeast Fairbanks Census Area | AK | 94.4 | Relatively High |
| 40 | Lincoln County | MT | 94.3 | Relatively High |
| 41 | Bonneville County | ID | 94.2 | Relatively High |
| 42 | Taos County | NM | 94 | Relatively High |
| 43 | Deer Lodge County | MT | 93.9 | Relatively High |
| 44 | San Miguel County | CO | 93.7 | Relatively High |
| 45 | Beaverhead County | MT | 93.6 | Relatively High |
| 46 | Weber County | UT | 93.4 | Relatively High |
| 47 | Ouray County | CO | 93.3 | Relatively High |
| 48 | Cache County | UT | 93.1 | Relatively High |
| 49 | Utah County | UT | 93 | Relatively High |
| 50 | Camas County | ID | 92.8 | Relatively High |
Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties — a score of 95 means this county's expected annual loss from avalanche exceeds 95% of all other counties. See the methodology page for definitions. Download the full CSV for all 684 scored counties.
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