FORECAST SUMMARY: Wednesday June 28th, 2023, through Thursday June 29th, 2023
OZONE: Ozone concentrations are expected to be in the Good to low-Moderate range.
PM-2.5: PM-2.5 concentrations are expected to be in the USG to Unhealthy range.
FORECAST DISCUSSION:
The majority of Michiganders woke up to a continued blanket of haze and wildfire smoke this Wednesday morning. We are continually being impressed by the PM-2.5 values we are seeing at the monitors across the state this morning and overnight. A dense plume of smoke came down from these fires overnight and almost all of southern Michigan is dealing with the smoke with PM-2.5 values in the Unhealthy and Very Unhealthy range. PM-2.5 values will improve slightly throughout the day today, but many areas will still be above the alert threshold of USG and possibly into the Unhealthy range still.
Winds looks to shift throughout the day from southerly to more NNW as we approach the evening as two High-pressures look to set up to our north and south. Going into tomorrow, winds will mainly be southerly which has us concerned with the amount of smoke and PM-2.5 concentrations returning to the region from being blown down south the past few days. Many models and forecast guidance have Michigan in the USG to Unhealthy range tomorrow. It is because of this the Air Quality Alert is being extended through tomorrow, Thursday. Tomorrow morning, the forecast will be reassessed but as of now, it looks like enough of the wind shift will blow smoke concentrations out of our area Thursday night into Friday. As we approach Friday, however, Ozone may become an issue once more as clear skies will allow for Ozone to develop.
EXTENDED FORECAST: High-pressure sets up to our north and south, reversing the winds to southerly and providing warmer air. Wildfire smoke may still be an issue and Ozone looks to make a return going into the weekend.
Next Forecast Update: Thursday June 29th, 2023