Chiang Mai, claim the locals, has two seasons. A rainy one and a dry one. However, this doesn't take into account the temperature .. which can be quite compelling .. especially when riding a motorcycle or in a tuk-tuk in the evenings.
December - January
North Thailand can get cold, dropping to as low as 10 degrees centigrade. If you're from Norway then don't forget the sun block but for the rest of us that can be jacket weather.
At the very least pack some warm trousers and a thick jumper for visits to Chiang Mai between Oct and Feb. Alternatively you can buy yourself some warm clothes here since they are relatively inexpensive.
Brief Summary of Chiang Mai Weather
- From June to November it's around 30 degrees, humid, overcast, and rains a lot. Get caught in a downpour and you'll know the meaning of wet.
- Around October the rains get less frequent and in November the rain stops completely and the temp dips quite sharply.
- It remains cold until Feb when it starts to climb back up rapidly until it peaks out around April - May.
- The months March & June are extremely hot because there is no cloud cover.
Take a walk around the moat and you'll see a number of shops selling army gear.