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Khao Lak sits on Thailand’s Andaman coast in Phang Nga province, about 70 km (43 miles) north of Phuket. The climate is tropical monsoon, with a dry northeast monsoon from November to April and a wet southwest monsoon from May to October. Daytime highs hold between 30°C and 34°C (86°F to 93°F) every month, so what changes is rainfall, not temperature. For an overview of the whole area, start with our Khao Lak travel guide, then use this month-by-month breakdown to pick your dates.
| Month | Avg High | Avg Low | Rainfall | Sea Temp |
|---|---|---|---|---|
| January | 32°C (90°F) | 22°C (72°F) | 37 mm | 28°C |
| February | 33°C (91°F) | 22°C (72°F) | 22 mm | 28°C |
| March | 34°C (93°F) | 23°C (73°F) | 44 mm | 29°C |
| April | 33°C (91°F) | 24°C (75°F) | 126 mm | 30°C |
| May | 32°C (90°F) | 24°C (75°F) | 370 mm | 30°C |
| June | 31°C (88°F) | 24°C (75°F) | 404 mm | 29°C |
| July | 31°C (88°F) | 23°C (73°F) | 394 mm | 29°C |
| August | 31°C (88°F) | 24°C (75°F) | 411 mm | 29°C |
| September | 30°C (86°F) | 23°C (73°F) | 462 mm | 28°C |
| October | 31°C (88°F) | 23°C (73°F) | 342 mm | 28°C |
| November | 31°C (88°F) | 23°C (73°F) | 194 mm | 28°C |
| December | 32°C (90°F) | 22°C (72°F) | 60 mm | 28°C |
Khao Lak Weather in January and February
January is peak season. The daily high averages 32°C (90°F) and drops to about 22°C (72°F) at night, with around 37 mm of rain on 5 days. February is the driest month of the year, averaging 22 mm of rain over 4 days with a high of 33°C (91°F). Both months get 8 to 9 hours of sunshine a day and the Andaman Sea sits at 28°C (82°F), so this is the best stretch for calm, clear water and open Similan Island day trips. For a full season-by-season read, see our best time to visit Khao Lak guide.
Khao Lak Weather in March and April
March is the hottest month, with a daily high of 34°C (93°F) and about 44 mm of rain over 6 days. April stays hot at 33°C (91°F) and rain climbs to roughly 126 mm over 13 days as the monsoon builds from mid-month. Humidity rises through April, and the Thai New Year festival of Songkran falls around April 13 to 15, which we detail in our Khao Lak events and festivals guide. Similan Islands trips keep running until the park closes in mid-May, but April seas can turn choppy.
Khao Lak Weather in May and June
The southwest monsoon arrives in May. Khao Lak weather turns wet, with about 370 mm of rain on 23 days in May and 404 mm on 22 days in June. Highs ease to 32°C (90°F) in May and 31°C (88°F) in June. Rain usually comes as short, heavy afternoon downpours followed by clear spells, so mornings stay usable. The Similan and Surin Islands close to visitors from mid-May to mid-October to protect the reefs. Inland day trips still run, and our things to do in Khao Lak guide covers the ones that stay open.
Khao Lak Weather in July and August
July and August average 394 mm and 411 mm of rain respectively, spread over 21 to 22 wet days, with highs around 31°C (88°F). August often brings a mid-monsoon lull of several dry days, so it’s a cheaper time to visit if you can accept afternoon storms. Surf picks up on exposed stretches, and waterfalls such as Ton Chong Fa run at full flow. Which beach faces which wind depends on its position, and our Khao Lak beach areas guide explains each stretch.
Khao Lak Weather in September and October
September is the wettest month, averaging 462 mm of rain on 24 days, with the coolest daytime high of the year at 30°C (86°F). October starts easing, with about 342 mm over 22 days and a high of 31°C (88°F). Flooding can disrupt roads in September, and many resorts close for annual maintenance, so check availability in our where to stay in Khao Lak guide before booking. The Similan and Surin Islands reopen to boats around mid-October, and dive conditions improve from late October.
Khao Lak Weather in November and December
The dry season returns in November, with around 194 mm of rain on 16 days and a high of 31°C (88°F), though the first two weeks can still be showery. December is reliably dry and sunny, averaging about 60 mm of rain with a high of 32°C (90°F) and 8 to 9 hours of sun. This is the start of peak season, with hotel prices at their highest from mid-December through early January. Our Khao Lak travel tips and FAQ guide covers packing and arrival logistics for this busy stretch.
