Temperature and Clothing
The south-west monsoon usually arrives from India at the end of May and lasts until November, with rainfall generally being heaviest in September. The rainy season however does not mean drizzle for days on end. The normal pattern over recent years has been clear mornings (with better-than-dry- season visibility and mountain views), clouds in the afternoon and subsequent rain, dry evenings and occasional rain at night.
Year round the air in Chiang Mai is less humid than in other parts of the country and is the main reason why the air seems more pleasant here. Moreover, the temperature difference between day and night and between the seasons is greater than in the other regions, so a jacket is recommended for evenings. Please see the dress code section for details on what to wear.