best month in year 2014 to visit maccau,hongkong,shanghai,beijing

as i am from south India an am not used to colder climates,could you please suggest me the proper month in 2014 when it will not rain ,not be too hot,not cloudy,and of course not cold {only pleasant}season to visit the 4 mentioned stations in china?
i have heard that in Jan it is usually very cold.