What's the weather in Chengdu, Jiuzhaigou and Huanglong in Dec? Any snowing? Accomodation in JZG is ok?

It will be a little bit cold in CD city, with the average temperature of around 10C. While in Jiuzhaigou and Huanglong, it will be much colder and the lowest temperature may fall to -4C. In late Dec. it may snow.

There are many hostels in or around Jiuzhaigou scenic area, so it would be convenient. But for Huanglong scenic area, as I know, it will be closed in Dec.