We are going to China the middle of Mar., Beijing, Shanghai and Hong Kong. What will the weather be?

Beijing: Its average temperature will be 40 F to 60 F in the mid of Mar. There may have several cloudy days.
Shanghai and Hong Kong will be warmer than Beijing. The temperature will be 45 F to 70 F and 65 F to 70 F respectively. Although there will have several rainy days, it won't influence the sightseeing a lot.