Here is a link to last weeks classic annual MX at Mammoth Lakes, CA.
It is a week long event that shouldn't be missed the second week of June if you get a chance.
You can usually snowboard/snowskii until 4th of July. Last week's ski report was 7-14 ft last week.
https://www.youtube.com/watch?v=J7GtPbrBOqs&feature=player_embedded
Many claim the track to be their favorite ever ! Although at ~6500 ft you better acclimate early the previous if you're going to race.