FORECAST SUMMARY:
Monday, September 20th, 2021, through Friday, September 24th, 2021
Ozone: Ozone concentrations are expected to be mostly Good for much of Michigan.
PM-2.5: PM-2.5 concentrations are expected to be Good for the majority of Michigan, with some areas potentially reaching the Moderate threshold, but only for a short while.
FORECAST DISCUSSION:
After a pleasant Fall weekend, Michigan will have similar weather for most of today, Monday, until a cold front comes through Tuesday afternoon.
Upper-level temperatures are expected to be in the mid-teens Celsius for today and into tomorrow until the frontal boundary enters the region. After the boundary exits the region, upper-level temperatures plummet to near zero Celsius for the remainder of the week until Friday afternoon. Upper-level winds will be from the SSW for much of today, Monday and into tomorrow, Tuesday, until the front moves through and shifts the winds to northerly flow. This northerly shift in winds is the reasoning behind cooler upper-level temperatures and cooler surface temperatures.
Surface temperatures will be in the mid-60s to low-70s Fahrenheit today and tomorrow until the cold front comes through with cooler temperatures. After Tuesday, surface high temperatures will be in the upper-50s to low-60s Fahrenheit for much of the region. Surface winds follow a similar trend to upper-level winds with being from the SSW today and tomorrow, before shifting to NNW for the remainder of the week. The combination of cooler temperatures and northerly flow is the reasoning behind Good concentrations for Ozone. Along with the cold front moving through, the chance of rain increases as the front treks across the region. Much of Tuesday afternoon and Wednesday morning will have a high chance of rain for Michigan.
EXTENDED FORECAST:
Going into Friday and the weekend, another cold front quickly enters and exits the region by the time we reach Saturday morning. This front will increase the chances of rain while also clearing out the area in terms of any Ozone or PM-2.5 buildup. For that reason, concentrations should remain mostly Good.
Forecast updated by: Alec Kownacki, Monday, September 20th, 2021
Next forecast update: Friday, September 24th, 2021