The short answer
When to go to Khao Lak
The best window is December to February, when rain is lowest and seas are calmest for the Similan Islands, with November and March also workable. May to October is monsoon, with monthly rain of about 430 to 640 mm at nearby Takua Pa, rough seas and island closures. For older travellers, the dry months make boat boarding, waterfall paths and walking far safer; shoulder months are cheaper but need flexible plans.
Month by month
Khao Lak weather by month
| Month | High | Low | Rain | Verdict | What to expect |
|---|---|---|---|---|---|
| January | 33°C | 22°C | 62 mm | Dry and bright; the best weeks for sea and boat trips | |
| February | 33°C | 22°C | 45 mm | Driest month; calm seas for the Similan Islands | |
| March | 34°C | 23°C | 145 mm | Hot, with showers building late in the month | |
| April | 34°C | 24°C | 222 mm | Hottest and increasingly wet; seas begin to change | |
| May | 33°C | 25°C | 431 mm | Monsoon begins; heavy rain and the Similan park closes | |
| June | 32°C | 25°C | 457 mm | Very wet; rough seas and frequent boat cancellations | |
| July | 32°C | 25°C | 466 mm | Very wet; many tours stop | |
| August | 31°C | 25°C | 570 mm | Wet and rough; most island trips unavailable | |
| September | 31°C | 24°C | 636 mm | Wettest month; storms and flooding possible | |
| October | 31°C | 24°C | 529 mm | Still very wet; island boats resume late in the month | |
| November | 32°C | 23°C | 232 mm | Rain eases and the season starts; showers remain | |
| December | 32°C | 23°C | 78 mm | Dry, busy and pleasant; book ahead for the peak weeks |
Temperatures and rainfall are long-term monthly averages. Check the forecast a few days before you travel.
Seasons at a glance
Khao Lak seasons for families and seniors
The easiest months: January, February and December
- January: Dry and bright; the best weeks for sea and boat trips
- February: Driest month; calm seas for the Similan Islands
- December: Dry, busy and pleasant; book ahead for the peak weeks
Good, with small trade-offs: March and November
- March: Hot, with showers building late in the month
- November: Rain eases and the season starts; showers remain
Possible, with planning: April
- April: Hottest and increasingly wet; seas begin to change
Best avoided with parents or children: May, June, July, August, September and October
- May: Monsoon begins; heavy rain and the Similan park closes
- June: Very wet; rough seas and frequent boat cancellations
- July: Very wet; many tours stop
- August: Wet and rough; most island trips unavailable
- September: Wettest month; storms and flooding possible
- October: Still very wet; island boats resume late in the month
Useful answers
Best time to visit Khao Lak: FAQs
What is the best month to visit Khao Lak?
January, February and December are the best months to visit Khao Lak, with March and November also good. The best window is December to February, when rain is lowest and seas are calmest for the Similan Islands, with November and March also workable. May to October is monsoon, with monthly rain of about 430 to 640 mm at nearby Takua Pa, rough seas and island closures. For older travellers, the dry months make boat boarding, waterfall paths and walking far safer; shoulder months are cheaper but need flexible plans.
Which months should I avoid in Khao Lak with elderly parents?
May, June, July, August, September and October are the months to avoid with older travellers. Monsoon begins; heavy rain and the Similan park closes Very wet; rough seas and frequent boat cancellations
When does it rain most in Khao Lak?
September is the wettest month, with about 636 mm of rain on average. The hottest month is April, with average highs around 34°C.