Intend to travel to silk road from 12-25 Oct 2012, what is the weather?

The Silk Road covers several provinces, so it is hard to tell you what kind of things to take.
Generally speaking, you need to take the long sleeved clothes and even prepare some thick clothes, since it is probably a little bit cold in some provinces in China at that time.
The average temperature at that time is about 10 centigrade degree during that time.