We went in April so can't help with weather, but we enjoyed our stay. Especially the pandas. Oh and you must try a Sichuan Hot Pot.
We went to mountains near there but don't know if it is the same ones you would ski in. We went to the Mount Emei area and saw a lot of Buddhist culture - temples, monasteries, Giant Buddha of Leshan. We spent the night in one monastery but it was a bit Spartan and not something I would want to do in January. It was cold enough in April as we were up in the mountains.
Briefly saw Chongqing as we disembarked our Yangtze Cruise there. Must admit I wasn't overly impressed but, then again, I saw very little of it. We were on our way to Yangshuo which is lovely.