FORECAST SUMMARY: Monday, June 23, 2025, through Friday, June 27, 2025
Air Quality Advisory Remains in Effect for Monday, June 23, 2025
The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is continuing an Air Quality Advisory for June 23, 2025, for elevated levels of ozone in western counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, AQI Orange) range.
The Air Quality Advisory for Monday is in effect for the following Michigan counties:
Allegan, Berrien, Cass, Kent, Mason, Muskegon, Oceana, Ottawa, and Van Buren
OZONE: 8-hour average Ozone concentrations are expected to mostly range between Good (AQI Green) and Moderate (AQI Yellow). An Air Quality Advisory remains in effect during Monday where conditions could reach Unsafe for Sensitive Groups (USG, AQI Orange) in several western lake shore counties.
PM-2.5: 24-hour average Fine Particulate concentrations are expected to range from Good (AQI Green) to Moderate (AQI Yellow).
FORECAST DISCUSSION
For those who complained that summer was slow to arrive, the past weekend should put that complaint to rest. Temperatures in excess of 90 degrees and dew points hovering around 70 degrees kept the misery index near 100 degrees, despite breezy conditions. That trend will persist through Monday.
The main player for the weather, this week, will be a cold front currently extending from northwest Wisconsin down to the four corners area in the southwest USA. That front is expected to slowly drop through Michigan during Tuesday and stall out around the Michigan/Indiana border. While this will provide some minor heat relief, we not expecting any real air mass change. Conditions will remain humid with dew points near 70 with daytime temperatures in the mid to upper 80’s. The stalled front will also act as a focus for shower and thunderstorm development during the Tuesday-Friday timeframe. Conditions could be favorable for strong to severe storms. That front is then expected to lift north, during Friday, as a warm front.
In terms of Air Quality, we have actually been fortunate up to this point. Although an Air Quality Advisory remains in effect for Monday, high dew points have a tendency to reduce ozone potential, and the weekend’s high humidity has helped stunt elevated growth. As the before-mentioned front approaches and arrives during Tuesday, the expected cloud cover and rain potential, as well as continued high humidity, should keep conditions no worse than Moderate for the next few days.
Saturday appears to be the first day for clearer skies with still hot temperatures and slightly less humidity with dew points in the mid/upper-60’s. We will be in the same potentially dirty air mass, however, and the weekend forecast will be updated on Friday to access the potential for elevated ozone. Long ranges models are indicating that the first real change in air mass will not occur until around Tuesday of next week.
EXTENDED FORECAST:
Air Quality could be an issue, during the upcoming weekend, with continued heat and slightly less humidity.
Next forecast update: Friday, June 27, 2025