Replying to Drop in question

If I'm building this drop in just for winter, do I really need to build the transition and ramp as well with wood or can I just make those out of snow? But I don't know how snow will hold up with the tranny because I can see it just sliding off. And do i need turf on top or can I just put snow as a cover on top of the wood? I rather not build the tranny + ramp since it will just take up too much room when I'm not using it so I'll value/appreciate all suggestions/ideas that support my idea. +k for help.

tl;dr: I only want to build tower and slope, would making a snow tranny + ramp work?