Really, as a transplanted New Englander, even this year's "marginal" season is not bad at all by the standards we grew up with. Most areas (just checked Big Sky too) are 3/4 open, and melt out is not nearly as early or as dramatic as Eastern resorts due to higher elevations and dry air. All you need are 3-4 inches of powder on a decent base to have fun, and no reason that can't happen between now and next week. Enjjoy, and use LOTS of sunscreen!