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 two-to-three times weekly throughout the year, and when warranted, an Air Quality Advisory is issued. Below is the latest air quality forecast for Wisconsin.

Wednesday, August 13 - Tuesday, August 19, 2025

Ozone

Good (Green) to Unhealthy for Sensitive Groups (Orange) AQI levels.

Particle pollution (PM_2.5)

Good (Green) to Moderate (Yellow) AQI levels.

Short-Term Forecast Maps:

The black dots represent the approximate location of Wisconsin's air quality monitors. Read the forecast summaries below for further geographic information.

Short-Term Forecast (Days 1-3)

Updated Wednesday, August 13 - 1:25 PM

PM2.5 enhancements will linger on Wednesday thanks to residual surface smoke along with any smoke aloft that is able to mix to the surface during daytime heating. Otherwise, mostly pleasant conditions are forecast with lower temperatures and less humidity. Some light smoke might hang around for Thursday as high pressure moves across southern Hudson Bay. Southerly winds will then be on the increase from west to east later Thursday into Friday. This will increase heat and humidity, potentially leading to ozone enhancements along Lake Michigan, with the best rain chances to the north. In general, a mix of Good (Green) to Moderate (Yellow) AQI is forecast Wednesday and Thursday, with the potential to reach Unhealthy for Sensitive Groups (Orange) AQI ozone on Friday.

Extended Outlook (Days 4-7)

Rain chances will be on the rise over the weekend, especially for northern areas on Saturday before pushing further south on Sunday as a front drops in from the north. Models are then stalling this front over the state, allowing precipitation chances to continue through the remainder of the extended outlook. In general, this should mean mostly Good AQI, with some Moderate AQI readings possible. We’ll also need to keep an eye on the lake shore Saturday, as USG AQI ozone will be possible.

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].