Khao Lak: monthly weather and climate
Khao Lak · Western Andaman coast
Sea conditions in Khao Lak change considerably between the dry and rainy seasons. Rough waves make swimming dangerous during the rainy season, and the Similan and Surin Islands also have seasonal closures. If you want to visit the islands, your dates need to suit their opening periods as well as the weather.
Before choosing your travel dates
The opening and closure periods for the Similan and Surin Islands are existing seasonal guidance. They do not mean the islands open on the same dates every year. Match your island visit to the opening announcement for the relevant year.
The recommended travel period is November to April, but the monthly table rates November as not recommended and April as average. The dry season does not guarantee low rainfall or consistently good weather for travel.
When are the dry and rainy seasons?
- Best time to visit
- Nov–Apr
- Dry season
- Nov–Apr
- Rainy season
- May–Oct
- Hottest month
- Mar (34°C)
- Wettest month
- Sep (465 mm)
Monthly weather and climate
Compare the table below to see which months are hotter or wetter. These are historical climate averages; they do not provide a forecast for your travel dates or tell you whether swimming will be permitted or safe.
| Month | Travel rating | Temperature | Rainfall | Rainy days | Humidity | Sunshine hours | Sea conditions |
|---|---|---|---|---|---|---|---|
| January | ++ Very good | 22~32°C | 42 mm | 5 days | 76% | 9 hours | Calm |
| February | ++ Very good | 22~33°C | 30 mm | 4 days | 72% | 10 hours | Calm |
| March | + Good | 23~34°C | 70 mm | 6 days | 74% | 9 hours | Calm |
| April | ± Average | 24~34°C | 155 mm | 14 days | 78% | 8 hours | Calm |
| May | - Not recommended | 24~32°C | 345 mm | 22 days | 83% | 6 hours | Moderate |
| June | - Not recommended | 24~31°C | 340 mm | 21 days | 84% | 5 hours | Rough |
| July | - Not recommended | 24~31°C | 365 mm | 20 days | 84% | 6 hours | Rough |
| August | - Not recommended | 24~31°C | 400 mm | 22 days | 84% | 6 hours | Rough |
| September | - Not recommended | 24~30°C | 465 mm | 23 days | 86% | 5 hours | Rough |
| October | - Not recommended | 23~31°C | 370 mm | 22 days | 87% | 5 hours | Moderate |
| November | - Not recommended | 23~31°C | 210 mm | 15 days | 84% | 6 hours | Moderate |
| December | + Good | 22~31°C | 65 mm | 7 days | 78% | 8 hours | Calm |
| Month | Weather and travel advice |
|---|---|
| January | The dry season is in full swing. The northeast monsoon brings pleasant conditions for a beach holiday. |
| February | This is the driest month, with long hours of sunshine. Humidity is also at its lowest, with favourable diving conditions. |
| March | Temperatures rise, but the weather stays mostly dry. Brief showers are possible from time to time. |
| April | Heat increases and thunderstorms become more frequent as the season changes. The existing island-opening guidance lists the Similan Islands as accessible in April. |
| May | The southwest monsoon begins, bringing heavy rain and rough seas. The existing guidance lists this as the period when the Similan and Surin Islands close. |
| June | The rainy season brings frequent heavy rain and rough waves. Red flags may be displayed on beaches during this period. |
| July | The rainy season reaches its peak. Persistent heavy rain and rough waves make swimming dangerous. |
| August | Humidity is high, rain is heavy and seas are rough. Continued rain turns the surrounding landscape lush and green. |
| September | This is the wettest month of the year, with heavy rain, very rough seas and a risk of flooding. |
| October | Towards the end of the rainy season, rain decreases as the month progresses. Humidity, however, is at its highest. |
| November | Rainfall decreases as the dry season approaches. The existing guidance says the Similan Islands reopen in mid-November. |
| December | Dry-season weather continues, with pleasant temperatures and calmer seas. The peak tourist season begins. |