Thursday, June 27th, 2019 through Friday, June 28th, 2019
Ozone: 8-Hour average Ozone concentrations will be mostly Good to Low Moderate through Friday.
PM-2.5: 24-hour average Fine Particulate concentrations will also be mostly Good with some Low Moderate through Friday.
A weak frontal boundary will linger over Michigan throughout the weekend. The movement of that frontal boundary over the next few days is hard to nail down and that makes the forecast difficult.
This promises to be the most interesting weekend for forecasting, so far. There isn’t too much concern about Thursday. The wind pattern should keep ozone over Lake Michigan, but wind speeds are light enough that a late afternoon breeze could push a bit of ozone inland. It does not warrant any advisories, however.
Friday should have less potential for elevated ozone with higher wind speeds to mix the atmosphere and a better chance of cloud cover.
The weekend looks more problematic. Saturday will be cloudy enough to keep numbers in check. Sunday has the greatest chance to have elevated ozone. Since there are so many variables in the forecast, the regional forecasters have decided to have daily calls to discuss the each day’s forecast. As such, there will be update to this forecast on Friday.
Air Quality is expected to remain mostly Good to Moderate going into the weekend.