After a sunny cold weekend, the same weather pattern continues today with wall to wall sunshine and seasonable cold temperatures.   I don’t expect most of us will even see a cloud this afternoon.  Winds will be very light and therefore wind chills won’t be an issue. Clear skies tonight allow temperatures to fall into the lower 20s.

Forecasting issues begin late tomorrow afternoon as a pattern change, eventually leading to milder air, will first bring snow and perhaps a mixed bag of precipitation. Temperatures will be cold enough for frozen precipitation Tuesday night and Wednesday.  I do expect most areas of southern Maine to see enough snow to plow – over an inch and a half – with some interior towns seeing upwards of 5 inches or more.

The trick to the forecast Tuesday night and Wednesday is figuring out exactly how much precipitation falls and when any warmer air arrives at cloud level.  If falling snow hits a warm layer on the way down to us, it could melt and then refreeze into sleet.  There’s also a possibility of freezing rain depending on the exact temperature profile between where we live and where the snow is being created in the clouds.

The exact thermal structure of the atmosphere is critical to what types of precipitation fall to the ground,

The exact thermal structure of the atmosphere is critical to what types of precipitation fall to the ground.

The snow looks to start after sunset Tuesday and continue through the night and into Wednesday.  The timing of the precipitation means a slow Wednesday morning commute for some areas, and there could be delays and cancellations.

While there might be some light snow, or mixed snow, sleet and freezing rain later Wednesday and Wednesday night, I expect most of the snow to have fallen by 1 p.m Wednesday.

Snow will fall later Tuesday and end during Wednesday afternoon

Snow will fall later Tuesday and end during the afternoon on Wednesday.

Skies will slowly try to clear Thursday with more sunshine Friday and into the weekend. It won’t be very cold this weekend so skiing and other outdoor winter activities can take place in relative comfort, at least for mid-January.

You can follow my updates here and on Twitter @growingwisdom.

filed under: