I calculated the snow water equivalent (at least down here in Philly) as 18:1 (doing a melt from what was collected in my Stratus). And with the wind, dry arctic air, and dews in the low teens or less (I'm currently down to a dp of 12), much of the snow pack has been blowing around, and that means sublimation can come into play (even with temps below freezing), literally "evaporating" the snow (i.e., the water goes right from solid to gas in the bright sun).
I agree with the issues of scouring out that built-up cold air being a tall order. Will have to see how much of a warm nose happens Sunday (and where in the atmosphere it oozes in).