rufic

I'll be arriving in Tokyo on the 5th Dec 2011 and leaving on the 23rd Dec 2011. Is it too early in the season to go snowboarding? Do I need to book accommodation/flights to Sapporo or can I just wing it when I get to Japan? Where does the snow fall first? Can someone reassure me? I'm getting a little nervous that I have booked these flights too early because I saw a good deal. Cheers, Richard