I draw the line at playing right after a fresh snowfall of any more than 2 or 3 inches. Way too easy to lose discs in the snow, I don't play with ribbons (I already have enough of a noodle arm, I don't need external forces causing more distance drag on top of that) and spending 10-15 minutes kicking around a bunch of snow looking for my disc every time I lose one just isn't fun.
Give it a few days though, and it gets much more playable - braver souls than I will track down the snow in many parts of fairways, and if you get a day or two of sun, it kind of ices over the surface of the snow and melts a bit of it to the point where it gets less likely for a disc to dive through, and a clearer impact mark where it does. That, plus walked down snow is just less of a pain in the rear to navigate on foot.
Eventually though, enough overall snow accumulation (12"-18" or more is about my limit), even that which is semi-icy on the surface, just gets to be too much, and trudging through it, & trying to dig around for discs that do dive through, gets to be more trouble than it's worth.