Seasons in Chiang Mai & the north
The rain runs May to October
Which part of the country
It is rainy season in Chiang Mai & the north right now, and it runs May to October. The rain tends to come hard and short rather than all day, and it stays warm through it — so the thing to bring is a shell you can fold into a day bag, not a coat.
Going in September
The monsoon over the hills, wettest from July to September. It rarely rains all day, but roads and trails turn to mud.
What this means for your bag
A packable rain shell
Not a winter coat — it stays warm through the rain. A light hooded shell that folds into its own pocket ends up in the day bag instead of the hotel room.
See the Weather Protection packQuick-dry fabrics
Cotton takes two days to dry in this air and starts to smell before it does. Synthetics and merino wash in a sink and are wearable by morning.
See the Summer Sun Kit packInsect protection
Standing water means mosquitoes, and the ones out at dusk are the ones that matter. Repellent with DEET or picaridin, and long sleeves in the evening.
See the Health & Wellness packShoes that survive being soaked
Streets flood faster than they drain. Sandals or mesh trainers dry overnight; leather does not, and one wet pair means walking in wet shoes all week.
See the Active & Adventure pack
Build a packing plan around the season you are actually travelling in.