I am fairly certain they will remain open. Just to be safe I would call the day of. Rarely do they close in the middle of the season due to above freezing temperatures...but if it is raining, there will be a higher chance of Bittersweet being closed for the day. Hope this helps!
If you go to their website at http://www.skibittersweet.com/pages/home.cfm they post current conditions updated daily.
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