FORECAST SUMMARY: Monday, June 16, 2025, through Friday, June 20, 2025
Air Quality Advisory for Tuesday, June 17, 2025
The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is issuing an Air Quality Advisory for elevated levels of ozone for several counties along the Western Michigan lake shore. Pollutants within those areas could reach the Unhealthy for Sensitive Groups (Orange AQI) range.
The Tuesday Air Quality Advisory includes the following West Michigan counties:
Allegan, Berrien, Cass, Kent, Muskegon, Ottawa, and Van Buren
OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) and Moderate (AQI Yellow) for most of the state with several West Michigan lake shore counties expected to see USG (AQI Orange) during Tuesday.
PM-2.5: 24-hour average Fine Particulate concentrations are expected to range from Good (AQI Green) to Moderate (AQI Yellow).
FORECAST DISCUSSION
Although smoke advisories are no longer an issue for the meantime, we are getting into the peak season for ozone development. This will be the case for Tuesday, as all signs point towards the likely development of elevated ozone along several western lake shore counties. Elements such as wind direction, temperature, dew points, upper air conditions all point towards the likelihood that could see ozone concentration in the USG range along those counties. Cloud cover is uncertain during the peak heating hours of the day, but enough sun will likely be present to trigger the photochemical reactions necessary to generate ozone. As a result, we are issuing an advisory along the West Michigan lake shore counties to address that threat.
A surface front does eventually drop down over the area by Tuesday night. By Wednesday morning, we are likely to see a warm front to our southwest push northward through the southern counties setting up the area for potential severe weather by Wednesday evening.
A brief reprieve from the heat and humidity will take place on Thursday in the wake of the following cold front. High pressure ridging begins to build north and eastward into the region during Friday and by the weekend dew points will be back into the lower 70s and daytime highs will be back into the upper 80’s and lower 90’s with the heat index running even higher.
EXTENDED FORECAST:
Air Quality could be an issue with increasing heat and humidity during the upcoming weekend.