(FOX 2) - The air quality alert for unhealthy levels of particulate matter and ozone has been extended into Saturday, the Michigan Department of Environment, Great Lakes, and Energy said.
Elevated levels of pollutants that can cause respiratory issues and exacerbate breathing problems for some people with asthma or other illnesses. Michigan has been under an air quality alert for three days due to wildfire smoke from Canada drifting into the region.
Both PM2.5 and ozone are respiratory hazards with negative health effects from both short and long term exposure.
EGLE says their concentrations are expected to be in the Unhealthy for sensitive groups to unhealthy range for Saturday. Levels could occasionally reach very unhealthy levels in places, the department warned.
The alert includes all of Southeast Michigan and some mid-Michigan counties near Saginaw Bay.
A notice posted on EGLE's website said it was seeing improving air conditions around Michigan as of Friday. The department also said it didn't expect to see levels return to the very unhealthy category that was imposed on Wednesday and Thursday.
It did however say that smoke from Fourth of July festivities including from fireworks could compound the health issues associated with exposure to air contaminants.
Read: What the AQI colors mean
Clouds on Saturday and potential rain on Sunday could further reduce rates of ozone and PM25 this weekend.