Dry and still air, WW. It doesn't wind at all then and skies are cloudless. If weather goes towards depression; low-pressure area, then it gets warmer but it will bring clouds, winds and possibly snow too. Then it feels actually colder because of the wind. But of course when it's -20 or such alike you'd feel cold if you don't have good winter clothes. Covering face, feet and hands (fingers, toes, nose and ears) well is important because they're the first places that will get cold. Also, if you run, move, or do some sports outside cold will pinch you quite easily. If having an asthma it'll make it difficult to be outside for a long time. During winter the humidity inside houses gets also very dry and quite many need to use some moisturising lotions.
We have actually only a ridiculous 1 cm of snow in southern Finland now. So the frost line beneath the ground is very deep now. Snow could be also a well insulation for the ground, drainage and even to the buildings if it's collected like a shelter near to them (but of course the pipelines etc. are insulated and contstructed in a way they they're not depended of the frost line).
We've been waiting this actually quite a long time that forest machines could go working to the forests.
Now the frost line is deep enough. Otherwise the roots of the trees would suffer too much because of the weight.