FORECAST SUMMARY: Monday, December 15, 2025 through Friday, December 20, 2025
PM-2.5: 24-hour average Fine Particulate concentrations are expected to be Good (AQI Green) to Low Moderate (AQI Yellow).
FORECAST DISCUSSION
Being a weather geek and a numbers nerd, I ran some numbers to show what we already know. It’s been a cold December! In Lansing, the average high temperature for this time of year is 36 degrees. This year, however, the December temperature has only broken the freezing mark twice, and just barely. The average daily temperature has been 11 degrees below normal.
The last full week before the Christmas holiday promises to show a slight moderation in temperature. Mid-week temperatures are looking to reach the upper 30’s or even low 40’s, giving the accumulated snow pack a chance to melt, a bit. The seven-day forecast is not showing any major winter weather issues, although Thursday is showing rain tapering to snow showers during the night. Even without any new major snow events in the long-range forecast, it is a good chance that we will retain enough snow to have a white Christmas.
In terms of Air Quality, we begin the week with Good Air Quality. However, as we see some melting and the addition of moisture to the atmosphere, that increases the chances for Air Quality to creep into the Moderate range, during the week.
EXTENDED FORECAST:
Air Quality is expected to remain Good to Moderate entering the weekend. The next best chance for light accumulating snow occurs early next week.