I'm from Canada...where everyone lives in igloos (jk, our summers are fairly hot and winters are very cold).
depends where you live, really, but for the most part -6 isn't so bad, even though, for the most part, it doesn't get much colder where I am during the winter.
I was in fort st. John, a small town i nthe north of my province, and it got to -40 quite a few times.