FORECAST SUMMARY: Monday, December 27th, 2021, through Monday, January 3rd, 2021

PM-2.5:

PM-2.5 concentrations are expected to be Good for Michigan this week and into the weekend.

FORECAST DISCUSSION:

A majority of the Lower Peninsula was impacted by a system this morning, Monday, with wintry mix and ice conditions being the main threat. After this system exits the area, a High-pressure system sets up to the southwest and shifts winds to a more westerly direction. This is only short-lived as another clipper system approaches the region late Tuesday and early Wednesday bringing another round of mixed precipitation throughout Michigan. Friday brings another Low-pressure system and associated cold front just in time for New Year’s Eve, this will drop temperatures overnight, but they will quickly rise to the mid-30s for most of Michigan during the day. With the changing of wind direction and approaching clipper systems, PM-2.5 concentrations should not be an issue for most of this week. There could be, however, some pockets of hourly concentrations in the low-Moderate range dependent upon stagnation of air. As stated above, though, Michigan will be impacted by numerous systems this week altering wind direction, so overall 24-hour average for PM-2.5 will be in the Good range.

EXTENDED FORECAST:

A few models are suggesting there to be a Low-pressure system impacting Michigan this upcoming weekend, Saturday night into early Sunday morning. Most of lower Michigan will be in warm sector air so impacts would most likely be rain. But areas north of Gaylord, Michigan and into the Upper Peninsula will be in cold sector air and could have snowy impacts. With this still being days away, we will need more model runs throughout the week to understand the impacts and to give an accurate forecast. In terms of PM-2.5 concentrations, they are expected to remain Good for the extended forecast into next week and into the New Year.

Forecast updated by: Alec Kownacki, Monday December 27th, 2021. Next Forecast update: Monday January 3rd, 2022