West Yellowstone averages nearly 150 inches of snow a year and the season is long-usually from mid- to late-November to April, sometimes May. The grooming program doesn't cover all of that time frame (usually mid-December to late March), but there's usually snow to be found somewhere in the area. And along with the hundreds of miles of groomed trails, if you're into off-trail riding, there are numerous places to jump off the trail and boondock through the trees and play in wide-open meadows.
One of our favorite times to ride the trails around West Yellowstone is in late November and early December before the groomers go out. The powder is awesome along the trails and you don't have to worry about rocks and stumps. We were also able to ride late in the season last winter, well into April and even into early May.