Sapporo on December 10:
Average daytime high: 3 degrees
Average nighttime low: -4 degrees
Average depth of snow: 4 cmThere might be snow or might not. To give you an idea, below are the snow heights of past years on December 10:
2008: none
2007: 4 cm
2006: 22 cm
2005: 4 cm
2004: 19 cm
If there is no snow in Sapporo, you are likely to find it in slightly higher locations, such as the mountains around Sapporo or Niseko.