I pretty much toss December, though sometimes we can manage some small events there, and expect March to have some chances even if the snow melts away in a day or less. But some of that is probably recency bias because, other than 2009 and a decent event I think in 2013, I can't remember very many December snows, whereas March seems to have been littered with them over the past decade. We've seemingly had some pretty cold March's lately, but that might also be skewed by 13 and 14.