Weather in Thailand in December
Hot and wet or hot and dry?
December is high to peak season in Thailand and one of the reasons that is the case is because the weather is brilliant. Lots of sunshine down south, little rain and the temperatures are comfortable without being scalding or freezing.
Bangkok and Central Thailand
You shouldn't run into any rain whatsoever in Bangkok in December. Temperatures will swing between low 20s and low 30s Celsius and you can expect a lot of clear blue skies. Bangkok at its best.
Like Bangkok and Central Thailand, Ko Chang and the surrounding islands are lovely in December. Very little rain, with plenty of sunshine and comfortable mid-range temperatures. Crowding will become a bit of an issue as things build up towards Christmas and New Year.
Chiang Mai in December sees little rain and comfortable, almost cool daytime temperatures. Evenings can be cold and if you're trekking you will need at least a long-sleeved top — locals will be running around in leather jackets and 52 layers. A great time to explore Chiang Mai and beyond.
As with Northern and Central Thailand, temperatures will be about as moderate as it gets in northeast Thailand — even a bit chilly in the evenings — and they'll be little rain to speak of.
The only region that sees much rain in December, the Gulf Coast of Thailand sees a bit of rain — expect some rain every other day — but between the rain you'll get decent blasts of sunshine to help you recuperate. Despite the rain, December can be very busy, especially on Ko Tao and Ko Pha Ngan.
More glorious weather — and the crowds flock to it. In December on Thailand's west coast you can expect a lot of sunshine with just the very occasional shower. The weather is definitely better on this coast than the Gulf Coast — though not as good as on Ko Chang. Some islands, like Ko Phi Phi are packed to the rafters in December. A fine choice.