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.

Monday, September 16 - Sunday, September 22, 2024

Ozone

Good to Moderate levels.

Particle pollution (PM_2.5)

Good to Moderate 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)

The seasonably warm and dry conditions will continue through the short-term period, as general high-pressure remains rooted to our east and low-pressure churns to our west. Southerly flow with an easterly component is expected each day, allowing areas closer to Lake Michigan to feel a bit cooler. Moderate AQI ozone is forecast for eastern areas on Monday, before spreading west each day. Along with mostly clear skies, weakening winds overnight will allow for nocturnal inversions to setup, leading to early morning PM2.5 enhancements around more populous areas. Increased vertical mixing through the afternoons should be enough to keep most areas within the Good AQI PM2.5 range, but some Low-Moderate AQI PM2.5 will remain possible, spreading east through Wednesday.

Extended Outlook (Days 4-7)

While seasonably warm temperatures currently remain on tap through the extended period, it does appear that precipitation chances will be on the rise beginning Thursday and lasting through the weekend. Unfortunately, no significant precipitation is anticipated, so the abnormally dry conditions will continue to inch closer to drought conditions through the weekend. As has been the general theme throughout this pattern, a mix of Good to Moderate AQI ozone and PM2.5 is forecast to continue.

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].