HI , I am planning to be in Qingdao from 22nd Dec- 3 rd Jan . What kind of weather can I expect ?

Well, the average temperature during that time will be nearly 0C. So you need take along Long John, down jacket and other warm clothes.
It should be a good idea to walk around city, but you may feel cold and a little difficult to cover all the destinations there. Maybe the bus can also help you along the hiking travel.