The cold season is generally from November to February. In Bangkok this means it might get as cold as 60F at the coldest point of the night, but more likely 65F. In the day it might average around, say, 75F. Sometimes maybe as low as 70F and higher up to 85F. In Bangkok you will only notice about 1 to 3 weeks of unusually cool weather, and then it’s back to the normal heat you’re used to. It only gets hotter the further south you go.