FORECAST SUMMARY: Monday, December 19, 2022, through Tuesday, December 27, 2022
PM-2.5: PM-2.5 concentrations are expected to range from Good to Moderate.
FORECAST DISCUSSION:
Tis the Monday before Christmas, and Michigan may be in for a treat later this week. There is growing confidence of impactful snow for the Great Lakes region just days before the Christmas holiday.
To start off the week, however, relatively quiet weather is in store for Michigan as a High-pressure system is influencing the region with light winds and stable atmospheric conditions. This system will give way to a rather weak Low-pressure system to our north Tuesday into Wednesday. Northern Michigan may be more impacted by this system with potential snow showers, but southern Michigan will only feel a drop in temperatures as the frontal boundary traverses through the region. Things become more interesting as we approach the latter half of the week with the potential of a winter storm impacting the Great Lakes region. Model guidance is still being fine-tuned, but confidence is growing for impactful snow and blustery conditions Thursday evening through Saturday. Position and strength of the Low-pressure system will determine the exact amount and location of snowfall, with windy conditions becoming more likely. Due to this system, travel plans will be disrupted and need to be planned accordingly.
After the system passes and the Christmas holiday approaches, temperatures will be nearing the coldest of the season thus far with high temperatures only peaking in the teens in most areas. The strong winds throughout the weekend will drop wind chills to the single digits and even into the below-zero range. Temperatures look to rebound into the mid-20s on Monday with quiet weather returning to start next week with High-pressure in place to our south.
In terms of air quality, in the beginning half of the week, due to the stable conditions, atmospheric inversions are expected for the morning hours and may last into the afternoon. This will allow for PM-2.5 concentrations to rise into the Moderate range for a couple hours before dropping back down to Good, as winds slowly increase throughout each day. Tuesday looks to be the day with the highest potential of PM-2.5 concentrations reaching the Moderate range. The passage of the cold front Tuesday into Wednesday, however, will help to clean out any concentration buildup. As stated above, an increase in winds associated with the system later this week will keep particulate concentrations low and Good through the weekend.
EXTENDED FORECAST:
Breezy conditions last through the beginning of next week, which will help keep overall air quality Good.
Next Forecast update: Tuesday, December 27, 2022