When will ski resorts in the Philadelphia open for the ski season? See this list of projected opening dates for Philadelphia mountains. Important Note: Not all dates listed here are official and final; they are projected and subject to change. Sort the list by Opening Dates or Resort Name, 24 Hour Snow, Base Depth and User Rating. Check back for updates on when the lifts are set to start spinning at Philadelphia ski areas, and don't miss opening day at your favorite resort!