FORECAST SUMMARY: Sunday, June 18, 2023, through Monday, June 19, 2023
PM-2.5: 24-hour average Fine Particulate concentrations are also expected to be mostly Moderate with scattered USG.
OZONE: 8-hour average ozone concentrations are expected to be mostly Good increasing to Moderate.
FORECAST DISCUSSION: Smoke continues to dominate the forecast as hot, dry weather persists and wildfires continue to burn across Canada. Smoke over Michigan had been forecast to stay mostly elevated and that has been the case, for the most part. Friday night, however, we did notice a plume mixing down over Indiana and Ohio that seem to catch the southeast corner of Michigan giving those monitors some higher numbers. Saturday morning, those monitors were still running in the low USG range so I bumped up the local forecast to USG. Since the winds were pushing that air mass out of the area and the numbers dropped into the Moderate range by early afternoon, no Action Day advisory was necessary.
As of Sunday morning, monitors across Michigan are showing Moderate readings. Some local fires in northwest Indiana are creating USG conditions in that area, but it has not bled over into Michigan.
The smoke models are still forecasting the smoke to stay aloft, although as we saw Friday night, some pockets can mix down to the surface. I will revisit the conditions Monday morning and update the forecast, at that time. Should any areas start seeing higher concentrations, today, I will update those locations to USG and if the area is widespread and persistent, I will issue an Action Day advisory. But for the moment, I will hold to the Moderate forecast, across the state.
Ozone has been holding in the Good range. Since the current dry, hot weather pattern is expected to last into next weekend, expect this forecast to be updated frequently.
EXTENDED FORECAST: Air Quality should be generally Moderate with the potential for scattered USG going into the next work week.
Forecast updated by: Jim Haywood: Sunday, June 18, 2023
Next Forecast update: Monday, June 19, 2023