Department meteorologists use monitoring data and weather forecast models to predict Wisconsin's future ozone (O3) and fine particulate matter (PM2.5) air quality using the Air Quality Index (AQI). 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.
Tuesday, September 2 - Monday, September 8, 2025
Ozone
Good (Green) to Moderate (Yellow) AQI levels.
Particle pollution (PM2.5)
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 Tuesday, September 2 - 10:10 AM
Canadian wildfire smoke originating mostly from fires in Northwest Territories is being observed at the surface across much of western Canada Tuesday morning. As Low pressure strengthens over the Lake Superior/Hudson Bay region Tuesday into Wednesday, an associated cold front will move through the state from northwest-to-southeast. Behind this front, smoke impacts will be possible, but PM2.5 concentrations are expected to remain in the Good (Green) to Moderate (Yellow) AQI range. Although we’ll see a brief lull in activity later Wednesday into Thursday, a secondary low pressure system will be moving into the region. This could bring in another round of smoke late Thursday into Friday, but winds are expected to be quite active and should mitigate any advisory level concerns.
Extended Outlook (Days 4-7)
As mentioned above, we may see some surface smoke impacts continue through Friday morning, potentially leading to Moderate AQI PM2.5. However, cleaner and cooler air will be pushing in, likely leading to Good AQI beginning later Friday and lasting through the weekend.
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].