Wisconsin dense fog advisories
There are no dense fog advisories in Wisconsin right now. The last one was issued on October 24, 2026.
Fog will reduce visibility to a quarter mile or less, making driving hazardous.
Updated from the National Weather Service · lists refresh hourly; the live map loads current alerts directly from the NWS
Map data: NWS, OpenFreeMap, OpenStreetMap
Active dense fog advisories in Wisconsin
None right now. Other active alerts in Wisconsin: none.
Dense Fog Advisories in Wisconsin by year
Wisconsin averaged 66.1 dense fog advisories per year from 2016 to 2025, and has had 82 so far in 2026. The most recent was issued on October 24, 2026.
Counties with the most dense fog advisories
| County | 2016–2025 |
|---|---|
| Douglas County | 128 |
| Washington County | 125 |
| Rock County | 124 |
| Green County | 123 |
| Waukesha County | 122 |
| Walworth County | 119 |
| Sheboygan County | 116 |
| Dodge County | 115 |
| Jefferson County | 115 |
| Dane County | 113 |
What a dense fog advisory means
Dense fog can cause chain-reaction crashes on highways because drivers suddenly lose sight of the road ahead.
More about dense fog advisories and the national map →
What to do
- Slow down, use low-beam headlights and leave plenty of distance.
- Never use high beams in fog.