South Dakota ice storm risk

66 counties scored 1 rated Very High

Minnehaha County has the highest ice storm risk in South Dakota, scoring 99.1 out of 100 — rated "Very High" by FEMA's National Risk Index.

# County NRI score Rating
1 Minnehaha County 99.1 Very High
2 Codington County 94.8 Relatively High
3 Moody County 93 Relatively High
4 Lincoln County 90.3 Relatively High
5 Pennington County 82.6 Relatively High
6 Yankton County 82.2 Relatively High
7 Aurora County 81.9 Relatively Moderate
8 Brown County 81.7 Relatively Moderate
9 Davison County 80.4 Relatively Moderate
10 Brookings County 80 Relatively Moderate
11 Beadle County 79.2 Relatively Moderate
12 Lake County 77.9 Relatively Moderate
13 Roberts County 77.8 Relatively Moderate
14 Day County 76.1 Relatively Moderate
15 Charles Mix County 76 Relatively Moderate
16 Jackson County 74.8 Relatively Moderate
17 Hutchinson County 72.1 Relatively Moderate
18 McCook County 69 Relatively Moderate
19 Hanson County 68 Relatively Moderate
20 Union County 67.7 Relatively Moderate
21 Turner County 67.1 Relatively Moderate
22 Dewey County 65.2 Relatively Moderate
23 Deuel County 64.4 Relatively Moderate
24 Kingsbury County 63.7 Relatively Moderate
25 Brule County 63.5 Relatively Moderate
26 Jerauld County 63.2 Relatively Moderate
27 Grant County 62.6 Relatively Moderate
28 Bon Homme County 62.4 Relatively Moderate
29 Douglas County 62.1 Relatively Moderate
30 Clay County 61.9 Relatively Moderate
31 Hamlin County 60.5 Relatively Moderate
32 Spink County 59.3 Relatively Low
33 Gregory County 57.9 Relatively Low
34 Todd County 57.7 Relatively Low
35 Hughes County 56.5 Relatively Low
36 Meade County 56.4 Relatively Low
37 Tripp County 55.1 Relatively Low
38 Marshall County 54.7 Relatively Low
39 Sanborn County 53 Relatively Low
40 Clark County 51.3 Relatively Low
41 Edmunds County 51 Relatively Low
42 Miner County 50.9 Relatively Low
43 Faulk County 46.3 Relatively Low
44 McPherson County 45.3 Relatively Low
45 Ziebach County 43.7 Relatively Low
46 Perkins County 40.2 Relatively Low
47 Lyman County 37.8 Relatively Low
48 Corson County 37.4 Relatively Low
49 Hand County 36.2 Relatively Low
50 Haakon County 33.6 Relatively Low
51 Mellette County 33.1 Relatively Low
52 Hyde County 32.3 Relatively Low
53 Stanley County 31.8 Relatively Low
54 Buffalo County 31.7 Relatively Low
55 Jones County 31.5 Relatively Low
56 Potter County 31.3 Relatively Low
57 Harding County 28.7 Relatively Low
58 Walworth County 27 Very Low
59 Bennett County 26.5 Very Low
60 Sully County 24.2 Very Low
61 Campbell County 21.6 Very Low
62 Butte County 21.3 Very Low
63 Fall River County 12.7 Very Low
64 Oglala Lakota County 11.9 Very Low
65 Lawrence County 8.3 Very Low
66 Custer County 3 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.

Ice Storm risk nationally:

Other hazard risks in South Dakota:

Frequently asked questions

What is the highest ice storm risk county in South Dakota?

Minnehaha County, SD has the highest ice storm risk in South Dakota, with a FEMA National Risk Index score of 99.1 out of 100 (rated "Very High").

How many counties in South Dakota are rated Very High for ice storm risk?

1 of 66 scored South Dakota counties are rated "Very High" for ice storm risk by FEMA's National Risk Index.

What causes ice storm risk in South Dakota?

Ice storm risk covers damaging freezing rain and sleet accumulation, which collapses power lines, trees, and structures. The highest-risk counties cluster in a band from eastern Texas and Arkansas through the Carolinas and New England, where warm Gulf moisture overruns cold arctic air most frequently. Ice storms cause catastrophic and long-lasting power outages. Ice storm and sleet events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.