^^ both good points. Fortunately, here on the front range, we probably get 5-10 nights a year that go below -5 and I don't know if I've ever seen the high temp for the day be below 0 F here. Even then, if it's that cold, the change of it being sunny is about 99% and the sun in CO is intense, even in the winter. In fact, my favorite winter trick is to pull the Leaf out of the garage and into the sun while I eat breakfast. When I'm ready to leave for work the temp inside the car is usually up by 10-20 F. That may not be a lot, but between that, the low relative humidity here and the seat heaters, running a Leaf in the winter isn't that painful. And as noted, the traction is probably about as good as nearly any FWD car with decent tires.
On the down side, the roads in CO tend to have a lot of crud on them when it snows and right after. There is virtually no salt used since the sun usually melts the snow off in a few days and while the roads are snowy , the efficiency is horrible.