what will be weather during 15-19 October, 2012 in Chengdu; things to do there.

Generally speaking, the temperature there is about 10C to 15C, so I think you need to take long sleeved clothes and coat.
As for the things to do, besides the local attractive spots such as the Research Base of Gaint Panda Breeding and Mount Qingcheng. Jiuzhaigou and Huanglong are the must seeing places nearby. Also you can go to Jilin Street to enjoy the local people's life at night.