Krabi in the rainy season: what stays open, and how to read an alert

From May to October the southwest monsoon reaches Krabi's west-facing coast. Most of what you came for is still there: island tours run, Railay can still be reached, the days inland do not need a boat. What changes is that a few places close on fixed dates, set by the Department of National Parks, and that any boat can be cancelled when the sea is rough.

This article sets out what closes, what keeps running, and how to read a weather alert, so a cancelled boat costs you a morning rather than the trip. For the rain month by month, and how the dry season compares, see the companion piece on when to visit.

What closes, on fixed dates

These are the closures in the Department of National Parks' table dated 7 January 2026. The department sets the dates every year, so check them for the year you travel. The dates of 16 May to 15 October you may read elsewhere come from the Similan and Surin parks further north (which close from 16 May to 14 October), not from the Krabi parks.

Many operators say Koh Rok and Koh Haa are closed from May to October or November. That is the season when trips there rarely leave because of the sea, not the official closure, which is shorter.

What keeps running

The island days. The four islands and the Hong Islands have no annual closure, and the tours keep running through the rainy season. Any departure can be cancelled when the sea is rough.

Phi Phi. Day tours keep running all season; in August and September they skip the landing at Maya Bay. The ferries from Ao Nang run all year, with fewer departures in the low season, and are cancelled when the sea is too rough.

Railay. The longtails from Ao Nang can be suspended on rough days. The crossing from Ao Nam Mao to Railay East, on the sheltered side, is the one described as most reliable from May to October.

Koh Lanta. Most boats stop after April, but the van and the vehicle ferry from the Hua Hin pier on the mainland (not the beach resort of that name) run all year.

The days inland. Tiger Cave Temple, the Emerald Pool and the hot springs are reached by road, so a rough sea does not cancel them.

Climbing at Railay. The main season is November to April, but climbing guides say you can still climb between the showers the rest of the year.

Tiger Cave Temple, the Emerald Pool and the hot springs

How to get to Railay, including in the monsoon

What the rain makes harder

Swimming. Box jellyfish and rip currents are both more common in these months, so the swim depends on the day: the beach flag, below, tells you whether to go in.

The Railay viewpoint trail. A climb on ropes and red mud. Do not try it in the rain or after rain.

Dragon Crest (Khao Ngon Nak). One local guide warns that the trail turns into a stream in heavy rain, and that the summit is exposed to lightning.

Jellyfish, red flags and where to swim

How to read an alert

Three bodies are involved, and only two of them decide. The Thai Meteorological Department forecasts and warns: it publishes a seven-day forecast and warnings that name the provinces at risk. On 27 August 2026, for example, it warned 27 provinces of heavy rain, and its bulletin of 28 August still described the monsoon as active over the Andaman Sea. When you read one, look for two things: whether Krabi or the Andaman Sea is named, and any mention of high waves. In the monsoon the Andaman can raise waves of 2–3 metres, higher in thunderstorms.

Then the Krabi harbour authority decides whether boats may go out. On some monsoon days it stops them altogether, and when it does, no tour and no ferry leaves, whatever you booked and with whom. Last, the operator decides for its own boat, even on a day when the harbour lets boats out. One Railay shuttle operator, for instance, says it stops its boats when waves pass two metres.

On the beach, the alert is the flag. A red flag, raised by the national park in wind and swell, means swimming is dangerous that day.

Planning a rainy-season trip

Keep a spare day. If one boat trip matters to you, do not leave it for your last day: put it early in your stay, so a cancellation can move to another morning.

Read the cancellation terms. Some tour pages say in writing what happens when the weather cancels the trip. The small-group James Bond Island and Hong day and the half-day climbing class at Railay both say you are offered another date or a full refund. Check what your own booking page says before you pay.

Leave slack at Railay. If you are sleeping on the peninsula, leave room in your plans for the day you leave, and know that the crossing from Railay East to Ao Nam Mao is the one to try on a rough day.

Choose your base with the sea in mind. A base on the mainland keeps the days inland and the road within reach whatever the sea does.

James Bond Island and Hong, small group

Half-day rock climbing at Railay

Where to stay in Krabi, area by area

Read nextThe best time to visit Krabi, month by month ▸

Read nextHow to get to Railay (and back with your luggage) ▸