FORECAST SUMMARY: Tuesday, June 20, 2023, through Wednesday, June 21, 2023

OZONE: 8-hour average ozone concentrations are expected to be Moderate to USG.

PM-2.5: 24-hour average Fine Particulate concentrations are expected to be mostly Moderate.

FORECAST DISCUSSION: As the smoke threat diminishes somewhat, ozone is back on the radar.  Michigan experienced some widespread higher ozone concentrations during Monday and a scattered few on Sunday.  Unfortunately, the reporting software for our monitoring network was down Sunday and Monday and we could not verify the numbers for forecasting purposes.  The network is back up and it is clear that we are seeing elevated numbers, even with the eastern wind.  As such, I will be issuing an Action Day Advisory for tomorrow, Wednesday, for both sides of the state.

The weather forecast remains mostly unchanged: hot, dry and easterly winds.  The dew points are rising, so some moisture is coming in which could potentially trigger scattered afternoon showers. 

With the persistent dry weather, fires and smoke will continue to be a concern on top of the current ozone threat.  As such, I expect this forecast to be updated, daily.

EXTENDED FORECAST: Air Quality should be generally Moderate to USG through the week.

Forecast updated by: Jim Haywood: Tuesday, June 20, 2023

Next Forecast update: Wednesday, June 21, 2023