Best time to visit
Thailand in May
The inversion begins. Koh Samui is the driest place on this site in May, at 113mm, while Phuket takes 269mm. If you want a beach this month, go to the Gulf.
Measured, not repeated
Where it rains in May, and how much
Driest first. Koh Samui takes 113mm this month and Phuket takes 269mm, which is 2 times as much. The strip on the right is that place's whole year, with May outlined, so you can see whether this is a good month for it or merely a bad one everywhere.
- Koh Samui 113mm 21 rain days
- Chiang Mai 135mm 16 rain days
- Bangkok 148mm 21 rain days
- Thailand's islands 243mm 24 rain days
- Krabi 255mm 27 rain days
- Phuket 269mm 25 rain days
ERA5 reanalysis, 1995 to 2024, averaged per calendar month at each place's own coordinates. A rain day is a day with a millimetre or more.
This is the month the country stops having one season. The southwest monsoon reaches the Andaman coast and Phuket records 269mm across twenty-five rain days, the second wettest month of its year. Krabi takes 255mm. On the other side of the peninsula Koh Samui takes 113mm, which is less than Bangkok's 148 and less than Chiang Mai's 135.
Rain days qualify that. Koh Samui has twenty-one of them in May, only four fewer than Phuket, but a third of the rainfall. The Gulf in May is frequent light rain rather than the tropical downpour the Andaman is getting, and that is a different holiday.
May is also the start of low season prices on the Andaman, and the two facts are connected. Whether that is a bargain depends entirely on whether you were planning to be outdoors.
Where to go in May
The three driest places on this site this month, in order.
What is on in May
-
Visakha Bucha
May, on the full moon date moves each year
The most important day in the Buddhist calendar and a public holiday. Alcohol sales stop.
-
Royal Ploughing Ceremony
May · Sanam Luang, Bangkok date moves each year
The date is set each year by the palace.