High ozone levels lead to air quality alert issued for Metro Detroit

An air quality alert was issued for Monday in Metro Detroit, and another one for Tuesday in West Michigan, with elevated levels of ozone as the underlying cause. 

The Michigan Department of Environment, Great Lakes, and Energy declared the Southeast Michigan alert at 9:18 a.m. Monday, the National Weather Service in Detroit says. It will remain in effect throughout the day for Livingston, Oakland, Macomb, Monroe, St. Clair and Wayne counties; including the cities of Detroit, Ann Arbor, Howell, Port Huron, Monroe and Warren. 

This is the first air quality alert for Southeast Michigan in 2026, issued at the start of a dangerous heat wave. 

"Dewpoints above 70 hinder ozone development. So while today is hot and uncomfortable, it's still just below that to allow increased ozone levels," CBS Detroit chief meteorologist Ahmad Bajjey said.

State officials have since invoked an air quality alert for West Michigan on Tuesday, according to the National Weather Service in Grand Rapids. The affected counties are Allegan, Berrien, Kent, Muskegon, Ottawa and Van Buren. This includes the cities of Benton Harbor, Grand Rapids, St. Joseph and Niles.

"There is the potential for multiple high ozone days this week," said EGLE Meteorologist Alec Kownacki. "So, we will be diligently tracking weather patterns into the weekend and calling alerts as necessary."

Ozone is a pollutant that can form in the atmosphere when various compounds mix in the air, EGLE said. Warm, sunny days contribute to harmful levels of ozone being created.

During an air quality alert day, state environmental authorities recommend to avoid strenuous outdoor activities as much as possible, especially people who have existing health conditions such as heart disease or asthma. "Watch for symptoms that include wheezing, coughing, chest tightness, dizziness, or burning in nose, throat or eyes," the alert said. 

Activities that can lead to ozone formation, and should be avoided during an alert, include refueling vehicles, using gasoline-powered lawn equipment, and using charcoal lighter fluid. Activities that are encouraged include telecommuting, delaying or combining errands and using water-based paints. 

Michigan's air quality monitoring network includes over 100 air monitors across 40 locations.