In the winter there are fewer tourist places open, but the outstanding scenery doesn't stop. There are too many photos to show it all here, but here's a great one.
From the Tagish River Bridge towards house.
Winter is the best time for viewing Northern Lights
February is time for the 1600 km long Yukon Quest Dog Sled Race
As for activities, there are many depending upon how adventurous you feel. From the commercial Takhini Hot Springs, natural Liard Hot Springs to the untouched Atlin Warm Springs.
Cross country skiing and even winter camping in a tent! Of course you can still do the multiday roadtrips without tenting, the minivan has a remote starter to keep it warm.
Tenting in the snow:
Or, camping in a warm van on a roadtrip
Caribou rush hour
Liard Hot Springs in winter
Atlin Warm Springs:
Daytime
And night time: