It’s been a pretty typical December so far. Snowfall and temperatures have been about average. When you compare it to last year, the final month of the year seems very wintry, but this is closer to the way December is supposed to be.

Averages are made up of extremes and we are entering a period of extreme weather over the next several days.  This is going to bring the coldest air of the season, more snow, high winds, a burst of warm weather and then more cold.  By the time you head to work Monday of next week the weather may be the top subject on many peoples mind.

A summary of the active weather pattern shows the snow, cold and wind that is coming.

When we get this type of extreme weather the subject of climate change often comes up.  I am not going to get into a big discussion about this here, but although it’s difficult to tie these individual events directly to climate change, computer models do forecast more such extreme events in a climate-changed world.

A wind chill warning is posted for the mountains tonight and early Friday.  Wind chills could be as low as -40 degrees during some of the highest wind gusts.  Along the coastline and into the foothills there is a wind chill advisory.  The cold and the wind will combine here to make it feel like -15 to -20 degrees overnight and early Friday.  We don’t see wind chills at this level much around here and you can get frostbite easily on exposed flesh like your face so just be smart about being outside the next 24 hours.

Low wind chill can cause frost bite in under 15 minutes in some cases.

Tonight, temperatures will drop to zero or a bit below along the coast and even colder in the mountains.  That wind will really bring a bite to the air.

Cold weather will be felt across all 6 New England states Friday.

Friday is the coldest day since last February.  Temperatures will struggle into the teens at the coast and remain in the single numbers in the foothills and mountains.  This is cold and it is early for this type of cold.

Warmer air starts to move north Friday night and Saturday.  As it hits all this arctic air, it will be lifted over it, form clouds and eventually snow.  This won’t be a big storm, but if you are planning on shopping Saturday expect slow going on the roads.

Image shows snow (blue) moving into area early Saturday and then ending as rain (green) late Saturday.

Eventually, the warm air will win and the snow will transition to rain with a period of mixed precipitation and freezing rain in-between.  Ski areas will also see rain, but not enough to damage conditions too much.

Another plowable snow event is likely Saturday morning and early afternoon.

Sunday is mild and wet, especially in the morning.  Later in the day a cold front sweeps back in the arctic air.  Highs return to below-average levels to start next week, but turn milder as we head for Christmas.

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