Mammoth. They're just about to open the whole mountain ...
This. Opening all lifts and trails this Fri. Already 113" of snow fall this season at the base at main lodge (almost half of last season's crappy total of 263"), and usually get 20+% more snow on top. The 18.5 foot tall sign post on the top is almost covered- about 4 feet remains uncovered.
It'll probably easier to access Tahoe and Utah, but these are easily the best current conditions in the west for sure.