Wisconsin cold wave risk
Milwaukee County has the highest cold wave risk in Wisconsin, scoring 100 out of 100 — rated "Very High" by FEMA's National Risk Index.
| # | County | NRI score | Rating |
|---|---|---|---|
| 1 | Milwaukee County | 100 | Very High |
| 2 | Dane County | 99 | Very High |
| 3 | Marathon County | 98.4 | Relatively High |
| 4 | Kenosha County | 98.3 | Relatively High |
| 5 | Marinette County | 98.3 | Relatively High |
| 6 | Sawyer County | 98.2 | Relatively High |
| 7 | Brown County | 98.1 | Relatively High |
| 8 | Waukesha County | 97.4 | Relatively High |
| 9 | Florence County | 97.1 | Relatively High |
| 10 | La Crosse County | 96.8 | Relatively High |
| 11 | Racine County | 96.1 | Relatively High |
| 12 | Vernon County | 96 | Relatively High |
| 13 | Monroe County | 95.8 | Relatively High |
| 14 | Outagamie County | 95.5 | Relatively High |
| 15 | Winnebago County | 95.3 | Relatively High |
| 16 | Forest County | 95.1 | Relatively High |
| 17 | Barron County | 94.7 | Relatively High |
| 18 | Douglas County | 94.7 | Relatively High |
| 19 | Oneida County | 94.5 | Relatively High |
| 20 | Vilas County | 94.5 | Relatively High |
| 21 | Wood County | 94.3 | Relatively High |
| 22 | Rock County | 94.1 | Relatively High |
| 23 | Eau Claire County | 94 | Relatively High |
| 24 | Shawano County | 93.3 | Relatively High |
| 25 | Langlade County | 92.9 | Relatively High |
| 26 | Clark County | 92.5 | Relatively High |
| 27 | Waupaca County | 91.6 | Relatively High |
| 28 | Fond du Lac County | 90.9 | Relatively High |
| 29 | Adams County | 90.4 | Relatively High |
| 30 | Polk County | 90.4 | Relatively High |
| 31 | Washington County | 90.2 | Relatively High |
| 32 | Lincoln County | 90 | Relatively High |
| 33 | Chippewa County | 89.5 | Relatively High |
| 34 | Ashland County | 88 | Relatively Moderate |
| 35 | Walworth County | 88 | Relatively Moderate |
| 36 | Portage County | 87.7 | Relatively Moderate |
| 37 | Dodge County | 87.3 | Relatively Moderate |
| 38 | Sheboygan County | 87.2 | Relatively Moderate |
| 39 | Marquette County | 86.9 | Relatively Moderate |
| 40 | Oconto County | 86.7 | Relatively Moderate |
| 41 | Bayfield County | 86.2 | Relatively Moderate |
| 42 | Sauk County | 85.9 | Relatively Moderate |
| 43 | Manitowoc County | 85.8 | Relatively Moderate |
| 44 | Door County | 85.6 | Relatively Moderate |
| 45 | Jefferson County | 85.3 | Relatively Moderate |
| 46 | Juneau County | 84.6 | Relatively Moderate |
| 47 | Washburn County | 84.2 | Relatively Moderate |
| 48 | Rusk County | 83.4 | Relatively Moderate |
| 49 | Price County | 83.2 | Relatively Moderate |
| 50 | Lafayette County | 83 | Relatively Moderate |
| 51 | Burnett County | 82.9 | Relatively Moderate |
| 52 | Columbia County | 82.8 | Relatively Moderate |
| 53 | Ozaukee County | 82.8 | Relatively Moderate |
| 54 | Green County | 81.8 | Relatively Moderate |
| 55 | Grant County | 80.9 | Relatively Moderate |
| 56 | Taylor County | 80.9 | Relatively Moderate |
| 57 | Jackson County | 80.6 | Relatively Moderate |
| 58 | Trempealeau County | 79.1 | Relatively Moderate |
| 59 | Dunn County | 79 | Relatively Moderate |
| 60 | Green Lake County | 77.2 | Relatively Moderate |
| 61 | Waushara County | 76.5 | Relatively Moderate |
| 62 | St. Croix County | 76.4 | Relatively Moderate |
| 63 | Richland County | 75.8 | Relatively Moderate |
| 64 | Iron County | 72.2 | Relatively Moderate |
| 65 | Menominee County | 71.9 | Relatively Moderate |
| 66 | Calumet County | 71.5 | Relatively Moderate |
| 67 | Kewaunee County | 66.6 | Relatively Moderate |
| 68 | Crawford County | 66.5 | Relatively Moderate |
| 69 | Iowa County | 60.3 | Relatively Low |
| 70 | Pierce County | 58.3 | Relatively Low |
| 71 | Buffalo County | 55.5 | Relatively Low |
| 72 | Pepin County | 34.8 | Relatively 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.
Cold Wave risk nationally:
Other hazard risks in Wisconsin:
Frequently asked questions
What is the highest cold wave risk county in Wisconsin?
Milwaukee County, WI has the highest cold wave risk in Wisconsin, with a FEMA National Risk Index score of 100 out of 100 (rated "Very High").
How many counties in Wisconsin are rated Very High for cold wave risk?
2 of 72 scored Wisconsin counties are rated "Very High" for cold wave risk by FEMA's National Risk Index.
What causes cold wave risk in Wisconsin?
Cold wave risk captures expected losses from extended periods of extreme cold, including wind chill. The northern Plains, Great Lakes, and interior New England see the most severe and frequent cold events. Cold extremes cause significant excess mortality, especially among unhoused populations, the elderly, and those with inadequate heating or insulation. Cold and wind chill events are reported at forecast-zone level in NOAA Storm Events and are not included in county-level counts.