FORECAST SUMMARY: Friday, May 17, 2024, through Saturday, May 18, 2024
Air Quality Advisory for Saturday, May 18, 2024
The Air Quality Advisory is in effect for the following Michigan counties: In West Michigan:
Allegan, Kent, Muskegon, Ottawa, Berrien, Cass, and Van Buren Counties
Ozone: 8-hour average Ozone concentrations are expected to be mostly Moderate (Yellow AQI), but locations along the western lakeshore and in the southeast may reach Unhealthy for Sensitive Groups – USG (Orange AQI) on Saturday.
PM-2.5: 24-hour daily average Fine Particulate concentrations will range between upper Good and Moderate.
FORECAST DISCUSSION:
A weak system is moving through Friday and another boundary early Sunday; however, neither system produces a good airmass change. Levels of PM2.5 have been lingering in the low-Moderate range the past couple of days, and without a clean airmass moving in, readings are likely to remain in the upper-Good to low-Moderate range through the weekend.
Surface and upper-level temperatures begin increasing Friday, and the warming trend continues Saturday. While a few storms could develop across southern portions of the state on Friday afternoon, most of the state will remain dry. Ample sunshine is expected on Saturday. A calm wind starts the day, but then light winds with a southerly component develop. All these combined results in ozone-conducive conditions for Saturday. The areas of greatest concern are along the west Michigan lakeshore, from Muskegon south, and in southeast locations. Because of this, we have issued an Air Quality Advisory for Saturday, May 18, 2024, for some counties in both west and southeast Michigan. The timing of the highest ozone concentrations will be during the afternoon and into the mid-evening hours. It is recommended that, when possible, you avoid strenuous outdoor activities, especially those with respiratory diseases such as asthma.
There is a possibility that ozone-conducive conditions could linger into Sunday. Because of this, we will be updating the forecast tomorrow to detail the expected air quality conditions for early in the new week.
EXTENDED FORECAST:
Extended forecast models show a system moving into the state Monday which should bring clouds and chances for rain. Air quality levels higher than Moderate are not expected early in the new workweek.
Next Forecast update: Saturday, May 18, 2024