This is really nice, the snow looks as if it just hit a giant rock and scattered! The mountian in front, however, looks a bit smudgey. I suggest smearing that to make it blend with the snow to look more "rock-like". The mountains in the background are very realistic looking, but I do reccommend adding a hint of brown, like the front mountian. The forest at the bottom looks great, nothing there that looks out-of-place, but a cool effect in snowy or cold places in general is a foggy haze. The sky looks a tiny bit pixelated, it doesn't look very smooth, but the colors look great! If it is a tall mountain peak, I would reccommend maybe adding a thin cloud layer around the top.
All in all, this is a magnificent piece, nicely done ^^