Thailand by Month
Weather varies a lot by region in Thailand — pick a month for the full breakdown.
Thailand is long, so it has no single "season". The west coast (Phuket, Krabi, the Andaman Sea) and the Gulf islands (Koh Samui, Koh Phangan, Koh Tao) don't share the same rainy calendar, and the north is hot and dry early in the year and wet later. Each month below has a short summary, and every card opens a full page with weather, crowds and prices. To choose by destination, see also our guide to the seasons. When to fly to Thailand
January sits right in Thailand's classic high season — dry weather across almost the whole country, with the most pleasant temperatures of the year, especially in the north.
February is still part of the dry high season — one of the most weather-reliable months across the whole country, near the end of the relatively cool period up north.
March is a transition month — the dry high season is still going in the south, but in the north 'burning season' gradually begins, and temperatures start climbing everywhere toward the April-May heat.
April is the hottest month of the year across most of Thailand, and includes Songkran (Thai New Year) — usually mid-month. Burning season in the north is still ongoing.
May marks the start of the rainy season on the Andaman (west) coast — Phuket and Krabi. The Gulf islands (Koh Samui) are still in a relatively reasonable season at this time.
June continues May's pattern — rainy season on the west coast, still relatively reasonable on the Gulf islands.
July is exactly the month where it matters most to understand that 'Thailand' isn't one season: the Andaman side (Phuket, Krabi) is in full rainy season, while the Gulf islands are still relatively reasonable.
August shares the same seasonal pattern as July — the Andaman side in rainy season, the Gulf islands still reasonable.
September sits in the middle of rainy season across most of Thailand — not the first ideal choice, but not a reason to cancel a trip either. The Gulf islands (Koh Samui) are still relatively reasonable.
October is a tricky transition month: Phuket and Krabi start drying out toward the end of the month, while Koh Samui is entering its wettest season.
November marks the start of the dry high season on the west coast (Phuket, Krabi) — but right at this time, Koh Samui can still be wet, since its rainy season runs until December.
December is the peak of high season — dry across most of the country, pleasant temperatures, and New Year's celebrations that draw huge crowds and push prices up significantly.