Which parts of Thailand are driest in October?

None of them. October is the only month in the year with every region inside its wet window at once, which is why the choice is about which wet stretch is lifting rather than about finding dry weather. Almost every camp in Thailand trains under a roof, so the rain costs you a run rather than a session.

Month 10 of 12

October

The crossover month, and the worst month of the year to arrive without having picked a coast.

In October, train in Chiang Mai and Phuket. Think twice about Koh Samui, Koh Phangan and Hua Hin.

October is the only month of the year with no dry region in it anywhere. Every one of the ten is inside its wet window, which happens once because the Andaman side is in the last weeks of its stretch while the southern Gulf is in the first weeks of its own. Those two facts read the same on a chart and mean opposite things.

Which is why October rewards a decision and punishes a compromise. A trip that starts in Phuket and finishes in Samui is walking out of weather that is lifting and into weather that is setting in. Run the same trip backwards and it is the right way round. The north is the other answer: Chiang Mai closes its wet window this month and its air will not go until February.

10 regions

Inside the wet window

The months the region prints as its own wettest. Almost every camp trains under a roof, so this reads as heat, humidity and a quiet gym rather than as a cancelled session.

Phuketภูเก็ต

Calendar

Andaman coast

Camps

Chiang Maiเชียงใหม่

Calendar

Inland north and northeast

Camps

Paiปาย

Calendar

Inland north and northeast

Camps

Bangkokกรุงเทพฯ

Calendar

Central and eastern

Camps

Koh Samuiเกาะสมุย

Calendar

Southern Gulf

Camps

Koh Phanganเกาะพะงัน

Calendar

Southern Gulf

Camps

Krabiกระบี่

Calendar

Andaman coast

Camps

Pattayaพัทยา

Calendar

Central and eastern

Camps

Hua Hinหัวหิน

Calendar

Upper Gulf

Camps

Isaan (Northeast)อีสาน

Calendar

Inland north and northeast

Camps

The month either side

Dates that can move

Most trips can move by a fortnight and a fortnight is the difference between two of these pages. Both neighbours are worth reading before the dates are booked rather than after.

All twelve months

The month before
September
The heaviest month of the year on the central plains, and the one month where almost the whole country is wet at once.
The month after
November
The interior comes good, the air is still clean, and the southern Gulf is the one place to stay away from.