It will break.

Think about it... The bottom is only plywood. Even if it's reinforced with glass, snow can get hard as a rock.

In fact, it's worse than a rock. If you landed on a flat, bumpy rock, the drag would slow you down quickly, so you'll only have a few fast impacts. But snow/ice is slippery, so you'll hit a lot of very hard bumps at a very fast speed.

So yea, make sure the snow is soft.