South Dakota avalanche risk
Lawrence County has the highest avalanche risk in South Dakota, scoring 10.5 out of 100 — rated "Very Low" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Lawrence County | 10.5 | Very Low |
| 2 | Pennington County | 6.4 | Very Low |
| 3 | Fall River County | 4.8 | Very Low |
| 4 | Meade County | 2.6 | Very Low |
| 5 | Custer County | 2.5 | 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.
Avalanche risk nationally:
Other hazard risks in South Dakota:
Frequently asked questions
What is the highest avalanche risk county in South Dakota?
Lawrence County, SD has the highest avalanche risk in South Dakota, with a FEMA National Risk Index score of 10.5 out of 100 (rated "Very Low").
What causes avalanche risk in South Dakota?
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.