Prolonged exposure to wildfire smoke can have short- and long-term impacts on one's health, especially for those with chronic conditions, seniors, young children and pregnant women.

A gray haze from wildfire smoke could be seen in Cincinnati, and the entire state of Minnesota is under an air quality alert.

The Michigan Air Quality Division said as smoke from Canadian wildfires continues to threaten the upper Midwest, "monitors in the western (Upper Peninsula) showed a large increase surface concentrations, during Tuesday, as smoke mixed down, which sent PM-2.5 concentrations soaring into the Unhealthy and higher range."