The blizzard came at the end of the cold snap-we were below freezing 12/25 to 1/5 or something like that. it warmed after the storm, but the snowcover did last awhile
yeah in the past I always looked at President's Day as the end of anything that would be long lasting on the ground or even come at all. But the last few years have seen a March resurgence in snows and even snowpack (last year we had 10 inches and it hung around for close to a week)
almost impossible for ZR to accrete on the streets of NYC unless it's been bitter cold for days--ground is still generally warm this time of year as well.