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.

Friday, August 22 - Thursday, August 28, 2025

Ozone

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

Particle pollution (PM_2.5)

Good (Green) 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 Friday, August 22 - 11:10 AM

Low pressure will move across Ontario Friday before stalling over southern Hudson Bay on Saturday. As an associated cold front pushes northwest-to-southeast through the state, increasing cloud and precipitation chances are expected, with the best chances for storms/showers remaining across the northern half of the state from noon to midnight Friday. Mostly Good (Green) AQI is expected, but there is a chance for Low-Moderate (Yellow) AQI ozone to develop along the Lake Michigan shoreline from Sheboygan Co. south to Kenosha Co. The front will continue to work through southern Wisconsin on Saturday, likely clearing Kenosha Co. between noon and 3 PM. Breezy NW winds will be ushering in a taste of fall behind this front, with cooler than normal temperatures becoming established on Saturday and continuing into next week. Good (Green) AQI is forecast to continue over the weekend.

Extended Outlook (Days 4-7)

Good AQI is forecast through the extended period. Low pressure to our northeast will continue to weaken as high pressure drifts over the Midwest through mid-week. Currently, long-range models then suggest another frontal passage on Thursday, followed by another shot of cool, fall-like conditions.

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].