it just snowed a fair amount 3 days ago, and its been raining down here, so its probably still snowing up there... That should give it a boost into the beginning of may for most places. I'm hoping A-Basin will go at least until the beginning of June (they usually close July 4, but we've been having dry winters lately [w/ the exception of last year]). If you're willing to hike, there are a few glaciers that are ridable year round.