# Counties in Wisconsin by highest daily Air Quality Index (US EPA), 2013

All 32 values come from U.S. Environmental Protection Agency for 2013, so the places are comparable. 16 counties have no value for that period and are not ranked.

- Indicator id: `aqi_max`
- Unit: index
- Definition: Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.
- Source: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: highest daily AQI (https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual)
- Publisher page: https://invokely.ai/en/publishers/environmental-protection-agency
- Retrieved: 2026-10-12
- Citation: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/highest-daily-air-quality-index/wisconsin-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | Dodge County | 214 |
| 2 | Sheboygan County | 140 |
| 3 | Kenosha County | 133 |
| 4 | Door County | 126 |
| 4 | Manitowoc County | 126 |
| 6 | Kewaunee County | 119 |
| 7 | Walworth County | 115 |
| 8 | Jefferson County | 112 |
| 8 | Ozaukee County | 112 |
| 10 | Brown County | 108 |
| 11 | Outagamie County | 105 |
| 11 | Rock County | 105 |
| 13 | Columbia County | 101 |
| 13 | Milwaukee County | 101 |
| 15 | Dane County | 93 |
| 15 | Racine County | 93 |
| 17 | Fond du Lac County | 90 |
| 17 | Sauk County | 90 |
| 19 | La Crosse County | 86 |
| 20 | Eau Claire County | 84 |
| 20 | Forest County | 84 |
| 20 | Marathon County | 84 |
| 20 | Waukesha County | 84 |
| 24 | Ashland County | 80 |
| 24 | Taylor County | 80 |
| 24 | Vilas County | 80 |
| 27 | Grant County | 79 |
| 28 | Chippewa County | 75 |
| 29 | Barron County | 65 |
| 30 | Monroe County | 44 |
| 31 | Trempealeau County | 37 |
| 32 | Jackson County | 8 |