9 tours
Island hopping from Krabi
The four islands and the Hong Islands, by shared or private boat, from Ao Nang and Railay.
Planning · 21 October 2026 · 6 min read
The best time to visit Krabi, month by month
Rain is only half of it. What the southwest monsoon really changes in Krabi is the sea, and with it the boats that every island day depends on.
On this page 5
Come between November and April if your trip is built around boats and swimming; January and February are the driest months in the official averages. Come between May and October if you are flexible and do not mind losing a day to the sea. October is the wettest month of the year.
What follows is Krabi month by month, from the Thai Meteorological Department's averages, then what the monsoon changes at sea and on the beach, and which month suits which trip. What closes in the rainy season, and how to read a weather alert, has its own article.
Two seasons, one coast
Krabi's coast faces west, onto the Andaman Sea, and that is the side the southwest monsoon arrives from. The dry season runs from about November or December to March or April; the monsoon from about May to October. In 2026 the Thai Meteorological Department declared the start of the rainy season on 15 May.
That orientation is why the season matters more here than the rain alone suggests. On the west-facing beaches and on the crossings to the islands, the monsoon brings swell as well as rain, and swell is what stops the boats.
Month by month
The rainfall figures are the official monthly averages for Krabi over the period 1981–2010, from the Thai Meteorological Department. Newer averages for the Krabi station were not available when we checked. They describe a typical year, not the one you will get.
Over the year, that is 1,998.8 mm of rain on 165.9 rainy days on average. The closure dates are those of the Department of National Parks for 2026, and the department sets them every year: check them before you book a specific island.
| January | 32.0 mm, the driest month. Dry season: the seasonal boats to Koh Lanta run, and this is the heart of the months when trips to Koh Rok go. |
|---|---|
| February | 43.4 mm, on 4.5 rainy days on average. Much like January. |
| March | 98.3 mm. Still the dry season, but the rain starts to build in the averages. |
| April | 147.2 mm. The end of the dry season, and the last month of the seasonal boats to Koh Lanta. Trips to Koh Rok thin out in April or May. |
| May | 171.6 mm. The southwest monsoon arrives. Island tours keep running, but rough days start to cancel them. |
| June | 192.7 mm. Koh Rok closes on 1 June. |
| July | 201.1 mm. Monsoon. The longtails from Ao Nang to Railay can be suspended on rough days. |
| August | 266.3 mm. Maya Bay and Koh Haa close on 1 August. Phi Phi tours keep running, without landing at Maya. |
| September | 275.2 mm. Maya Bay, Koh Rok and Koh Haa stay closed until 30 September. |
| October | 323.5 mm, the wettest month, with 21.5 rainy days on average. Maya Bay reopens on 1 October. No boats leave Klong Jilad for Koh Lanta this month. |
| November | 179.7 mm, still a wet month in the averages. The seasonal boats to Koh Lanta start again. |
| December | 67.8 mm. The dry season settles in. |
What the monsoon changes at sea
In the monsoon the Andaman can raise waves of 2–3 metres, higher in thunderstorms, and on some days the Krabi harbour authority stops boats from going out at all. Island tours run through the rainy season; what changes is that any departure can be cancelled, and the decision is made on the day.
The crossings do not all react the same way: the sheltered one from Ao Nam Mao to Railay East holds up best, and most boats to Koh Lanta stop after April. Which boats keep running, crossing by crossing, is set out in the rainy-season article.
Krabi in the rainy season: what closes, and how to read an alert
How to get to Railay, in any season
What it changes on the beach
Box jellyfish are found off this coast, and the Tourism Authority of Thailand says they are more common during the monsoon, when wind and currents bring them closer to shore. In wind and swell, the national park raises red flags on the beaches, and rip currents are common in those months. For a holiday built around swimming, the dry months are the safer bet; in the rainy season, the swim depends on the day.
The plankton follows the season too: one local guide advises November to May for the bioluminescent plankton, when there is less rain and the water is clearer.
Jellyfish, red flags and where to swim
Which month for which trip
A beach and swimming holiday. December to March, the driest months in the averages and well outside the monsoon.
Maya Bay. Any month except August and September, when it is closed. Even then, Phi Phi tours run and pass by without landing.
Koh Rok. November to April. The island is closed from 1 June to 30 September, and in practice trips run mostly in the dry season.
Koh Lanta by boat. November to April. Outside those months, go by road and the vehicle ferry.
A flexible trip, with a spare day. May to October can work if a cancelled boat would not ruin your stay: the crossing to Railay from Ao Nam Mao is the most reliable one, and the days inland do not depend on the sea.
Whatever the month, where you sleep shapes how much the sea can disrupt you: a base with a sheltered crossing or a road out gives you more choice on a rough morning.
Where to stay in Krabi, area by area
Read nextKrabi in the rainy season: what stays open, and how to read an alert ▸
Read nextHow to get to Railay (and back with your luggage) ▸
Days out that go with this
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Phi Phi day trips from Krabi
Maya Bay, Pileh Lagoon and the Viking Cave by speedboat or catamaran, by day or at sunset, from Krabi.
Common questions
What is the best month to visit Krabi?
For calm sea and little rain, January and February are the driest months in the official averages for 1981–2010, and the dry season runs from about November or December to March or April.
What is the wettest month in Krabi?
October, with 323.5 mm of rain and 21.5 rainy days on average (official averages for 1981–2010), followed by September and August.
Can you visit Krabi between May and October?
Yes. Krabi stays open in the southwest monsoon, and island tours keep running, but any boat can be cancelled on a rough day and a few places close on fixed dates. Leave a spare day if one boat trip matters to you.
When do the boats to Koh Lanta run?
The boats from Krabi Town's Klong Jilad pier, and most boats from Ao Nang, run from November to April. The rest of the year, you go by van and the vehicle ferry, which run all year.