Weather
The most consistent month of the year. Andaman coast calm, Gulf coast dry, Bangkok 24–32°C, Chiang Mai cool in the morning.
Rain is rare but not impossible — a day or two in the south is normal even in high season.
Crowds and prices
Still peak until about 5 January, then prices fall by 20–30% and the beaches thin out. Mid-to-late January is the sweet spot of the whole year.
Where to go
Anywhere. This is the one month when the Andaman and the Gulf are both working, so you can pick based on what you want rather than the weather.
