Department meteorologists use monitoring data and weather forecast models to predict Wisconsin's future ozone (O₃) and fine particulate matter (PM_2.5) air quality using the Air Quality Index (AQI) [exit DNR]. This forecast is updated frequently, and when warranted, an Air Quality Advisory is issued. Below is the latest air quality forecast for Wisconsin.

Updated Monday, July 20 - 6:10 p.m.

Tuesday's Forecast (July 21)

Breezy northwest flow will lead to slightly below normal temperatures and much less humid conditions. Moderate (Yellow) AQI PM2.5 is likely to stick around statewide through the a.m. hours because of smoke from wildfires in Saskatchewan and Manitoba. Throughout the p.m. hours, we should see a trend towards Good (Green) AQI PM2.5 from north to south as a secondary front rolls through. The highest PM2.5 concentrations could be close to the Unhealthy for Sensitive Groups (Orange) AQI threshold and will be located in western Wisconsin.

Wednesday's Forecast (July 22)

High pressure will move over the state allowing seasonably cool temperatures and low humidity to continue. Winds will be out of the north to start the day, so we’ll monitor how fire activity in Minnesota/Ontario evolves on Monday and Tuesday. For now, we’ll continue the statewide Moderate (Yellow) AQI PM2.5 forecast, but statewide Good (Green) AQI is a possibility.

Thursday’s Forecast Trend (July 23)

Air quality is expected to degrade across northern Wisconsin due to wildfire smoke.

Forecast Maps:

The black dots represent the approximate location of Wisconsin's air quality monitors. The black borders approximate Wisconsin's Reporting Area boundaries on EPA's AirNow website [exit DNR].

Air Quality Index (AQI) ranges

For more information about AQI ranges and colors, see the U.S. EPA's Air Quality Index (AQI) Basics [exit DNR].