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.

Updated Monday, April 27 - 9:45 a.m.

Monday, April 27 - Sunday, May 3, 2026

Ozone

Good (Green) 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)

Good (Green) AQI is forecast throughout the short-term period. Low pressure will be moving through the state today (Monday), with widespread showers and storms expected. PM2.5 concentrations will be highest through the a.m. hours across southern Wisconsin before increased vertical mixing, gusty winds, and precipitation help to decrease concentrations through the p.m. hours. Breezy NW winds and cooler, near-normal temperatures are expected Tuesday. Northelry flow and at to slightly below normal temperatures are forecast Wednesday.

Extended Outlook (Days 4-7)

Good AQI is forecast throughout the extended period. The below normal temperature trend will continue into the weekend as a reinforcing high pressure air mass drops south from Canada Thursday. Frost/freeze headlines will be possible across southern Wisconsin both Friday and Saturday mornings to kick off the month of May. Slightly warmer temperatures and precipitation chances return for Sunday.

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].