Koh Samui weather

As is the case in most places around the world, the weather on Koh Samui is much less predictable than it used to be. There are still obvious wet and dry seasons, as well as hotter and cooler months but storms occasionally blow in and change the weather conditions overnight, so it's best to expect a little variation during a longer stay.

The warmest and driest part of the year begins in late December or early January and lasts until early May. These months are also the busiest for tourism as visitors are generally guaranteed sunshine for most of their holiday. May brings stronger winds and with them more cloud and occasional rain. Then storms arrive through June, and in July and August the rain falls more regularly, although rarely for more than a couple of hours a day and often in the evening or at night.

September is often a delightful month with plenty of sunshine, light winds and cooler temperatures. October is officially the start of Samui's rainy season, but this often arrives late so in reality, November is the only month when rain falls consistently. When they do, however, the downpours can be very heavy and flooding is common in low lying areas.

December sees the weather gradually improve again, as visitors begin to arrive with fingers crossed for sunshine at Christmas and New year. This is not guaranteed, sadly, but with January promising a return to blue skies and warms seas you don't have long to wait for more classic Samui sunshine.