December in Chiang Mai averages a daily high of 29.7°C. Rain is rare — about 0.8 wet days and 16.3mm across the month. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Chiang Mai is December–January.
Based on CHIANG MAI, TH (0.8km), 1995–2024. 13 years of December data.