After a mild weekend (Highs of -7 Sat & -4 Sun) , cooler air is set to return to the Capital Region.
Today's high of -8 will likely be the warmest we get for the rest of the week.  MAYBE even the rest of the month.'s not even going to FEEL like -8 today. (more like -15 to -20 thanks to wind chill.)

More on the tumbling temperature in a moment.

Haven't had any snow for a few days, so I guess we're due.
A low pressure system is set to push into southern Alberta today.  A trough will stretch north from that system & we'll get some snow in Edmonton tonight.
2-5cm looks likely for Edmonton.  
Heaviest snow (5-10cm by Tuesday morning) is expected to hit the Peace Country & areas SE into the Hinton/Edson region.
East-central & Northeast Alberta may get a few flurries, but no accumulating snow.
After tonight, there's another chance of snow late Thursday into Friday.  That could be a significant snow-maker for parts of the province too.

Ok...back to the cooldown:
Daytime highs are going to slip into the -10 to -15 range for Tues/Wed/Thur.
And then...they'll slide even further!
Average daytime highs for Dec 17-22 are in the -5/-6 range.
HOWEVER, a strange thing happens at Christmas.
Here are the average highs:
Dec 23   -4
Dec 24   -2
Dec 25   -2
Dec 26   -3

By December 28th, the 30-year average high is back to -7.  But for a couple days around Christmas, it gets warmer.
At the past 30 years it has.

This year is shaping up to be a different story.
The GFS ensemble is projecting daytime HIGHS in the -20s starting Saturday (dec 22) and continuing right through to next Thursday (dec 27).
After the 27th, we "warm up" to highs in the -15 to -20 range right through into early January.
Oh, and at this looks sunny for Christmas Day.  
So...the upside is that it may be COLD, but it won't be stormy.

Edmonton Forecast looks like this:

Today - Increasing cloud.  Chance of afternoon flurries.
High:  -8
Wind chill in -15 to -20 range this afternoon.

Tonight - Cloudy w/ snow.  2-5cm psbl
Low: -15

Tuesday - Light snow in the morning. Mostly cloudy in the afternoon.
High:  -12

Wednesday - Partly cloudy.
High:  -14

Thursday - Mostly cloudy.  60% chance of snow.
High:  -12

Friday - Mostly cloudy.  30% chance of flurries.
High:  -16

Saturday - Mix of sun & cloud.
High:  -21

Sunday - Partly cloudy.
High:  -22