What is the best time to visit Koh Samui?

The best time to visit Koh Samui is from December to February, which is the dry season. The temperature during this time is around 28 degrees Celcius, making it perfect for enjoying the beaches, watersports, waterfalls, and everything Ko Samui is known for. However, this is also the peak tourist season, so the prices tend to be higher.

Koh Samui has a tropical monsoon climate and remains warm and humid throughout the year. The average temperature throughout the year varies from 26-27 degrees Celsius but can cross 30 degrees during the hot summer months of May and June. October to late December is when the tropical rain lashes down on the island and is regarded as the wettest month of the year. The wet months are not the best time for scuba diving or bathing, but you can take recourse to plenty of activities.

Weather in Koh Samui


Upcoming Koh Samui Weather

Monthly Weather in Koh Samui

Month High/Low (°C) Rain
January 26°/ 23° 4 days
February 26°/ 24° 5 days
March 27°/ 25° 1 days
April 28°/ 25° 11 days
May 29°/ 25° 19 days
June 29°/ 25° 16 days
July 28°/ 25° 13 days
August 28°/ 24° 15 days
September 27°/ 24° 17 days
October 27°/ 24° 18 days
November 27°/ 24° 16 days
December 25°/ 23° 10 days

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More about Best Time to Travel to Koh Samui

Koh Samui in January

January is one of the colder months with temperatures falling to 26 degrees Celsius. The pleasant temperatures coupled with marking the end of the rainy season are reason enough to welcome the New Year on the beach island. Humidity is also not much of a concern during this month with an average of only seven rainy days in the month. The waters are warm to enjoy snorkelling, swimming, scuba diving and other water sports. Koh Samui is usually buzzing with tourists during this time of the year though it may get a bit peaceful later in the month. Some of the places to visit include the beautiful Lamai Beach, Chaweng beach, Maenam beach and more. With the advent of the peak season expect accommodation and tariff rates to be high.

Koh Samui in Peak Season

Koh Samui is mostly dry and satisfyingly warm from late December to early April which is also its peak season. The sea is calm, and the skies are clear though it is not surprising to witness a few occasional showers. The peak season is when throngs of tourist visit the island to enjoy the beaches and all related water and beach activities. It is also the perfect time for mountain biking, trekking through the forests, hiking and swimming. April is when the hot summer begins to set in with temperatures rising under the blaze of the sun.

Koh Samui in Shoulder Season

The months of May, June, July, August and September can be considered as the shoulder season for Koh Samui. May and June are the hottest months of the island, making sightseeing or enjoying the adventures of Koh Samui a tad bit harder under the heat of the scorching sun. The warm months also witness a slight increase in rainfall with a frequent pattern of sunny mornings followed by rains during the afternoons or evening. With an increase in rainfall humidity also increases and it is best to be equipped with mosquito repellants if you plan a visit during the shoulder season. The shoulder season is when most schools are open, making Koh Samui a quieter abode for tranquil travellers. The water activities are inviting in the heat, and so are the cool shades and bars along the beaches.

Koh Samui in Off Season

The months of October to late December are the wettest in Koh Samui and are hence regarded as off season for travellers. Rains are usually heavy or continuous with tropical cyclones common during October - November. Though these are the winter months, temperatures rarely dip below 25 degrees Celsius. The tropical weather is a big advantage for tourists from colder countries who find the warm winters a relief from the otherwise clenching chill. This is the period when accommodation is easy to find, and the tourism industry hits a lull period. However, there is a lot to do in the rainy season as well and the few hours of sunshine can be grabbed to shop for Christmas, laze on the beach or visit the island?s tourist spot.

Koh Samui in February

February is the driest and one of the most pleasant months to visit Koh Samui. The weather is just perfect for beach lovers, who may want to saunter on the beach or try out the various water adventures. It is also warmer than the preceding winter months with temperatures averaging at 27 degrees Celsius. February can be regarded as the peak month of the peak season to enjoy the white beaches of the island and enjoy a swim or sunbathe. Snorkelling, kayaking, coral reefing are also favourite activities in Ko Taen and other beaches of the island. On Valentine?s Day surprise your partner with a cruise to watch a stunning sunset or relax together with a couple?s massage. Dine a romantic dinner or walk hand in hand along the fantastic beaches to celebrate a memorable day or week of love. February is also usually when the Chinese New Year falls sparking up the island with parties, street lights and fireworks.

Koh Samui in March

March too remains dry, though the temperatures rise just a little. It is still pleasant weather and excellent for hiking, forest trekking, elephant trekking or mountain biking. The weather is inviting for outdoor activities, and the beach is shimmering and warm. The Na Mueang Waterfall hiking trail and the Secret Buddha Garden are some of the outdoor activities that one can try. Water activities continue to be a hit as expected in the peak season. The clear blue skies are welcoming signs to pay a visit to tourist landmarks of the island, such as the Wat Phra Yai where the enormous golden statue of Buddha resides or the Wat Plai Laem. The outdoor markets of the Fisherman?s Village Bophut are great for shopping souvenirs and dining. Makha Bucha Day a Buddhist festival takes place usually in March.

Koh Samui in April

April sets in with the foreboding of rising temperature. The average temperature in April is about 31 degrees, and there is very little rain expected in this month. The increase in heat and humidity makes travellers rush to air conditioned villas and places of stay, yet the waters are warm enough for pleasant swims. The month is not too ideal for outdoor activities such as hiking or trekking, though it is not impossible to give it a try. However, it is the Thai New Year Festival or Songkran which is the main attraction of this month. Despite the heat, tourists love to visit the island during April to be a part of Songkran?s celebrations. This three-day celebration across Thailand is a water festival that is filled with lots of fun and good spirit. The water fights are the highlight of the festivities and usually start in Chaweng a busy town of the island. The island is soaked up in parties, music, water fights and a frenzy that is palpable and infectious.

Koh Samui in May

During May the temperatures reach up to 33 degrees, and it is often the hottest month along with June closely followed by April. The high temperature also results in more rainfall and storms are quite a relief during this time. But, the plus point is that rain dries off quickly and water-based activities are plenty to alleviate the heat. For travellers who do not mind the weather too much, the shoulder season is a good time to visit Koh Samui as the island is much less crowded and quieter. Besides swimming or being under the water, there are other activities, such as, visiting a theatre, shopping in the many malls, getting a foot massage or enjoying a luxury spa that can make Koh Samui interesting in May. The Koh Samui Regatta began in 2002 and continues to be a renowned sailing experience with yachts from across Asia competing for the race. Many spectators and fans also make it a point to attend this sailing event that takes place at the end of May.

Koh Samui in June

June is hot with temperatures reaching up to 32 degrees. Rain is a welcome boon in the scorching heat, and the resorts and beaches are usually less crowded. It is a great time to enjoy the cool Thai drinks and relax in the beach restaurants. Like May, you can enjoy some swimming and diving to cool off or visit the air conditioned shopping malls and theatres to beat the heat. Keep the mosquito repellents in place since the humidity may attract them. By the end of June, an influx of tourists is expected as it is the beginning of the summer vacations in many parts of the world.

Koh Samui in July

July does see a spike in tourism as families with children make way for a holiday during the summer vacations. However, the humidity peaks during the afternoons and it is best to plan sightseeing during the mornings and evenings. The weather is still pretty hot, but the temperatures may not reach to those in May and June. The sky may begin to get overcast with temperatures varying from 29 to 32 degrees with around nine days of rainfall in the month.

Koh Samui in August

Just like July, August continues to be hot and humid with temperatures hovering around 28-32 degrees. It receives its fair share of rains, but you can find solace in the screened huts and restaurants of the beach in case it begins pouring while you are lazing on the beach. Plan sightseeing in the mornings, visiting the Wat Phra Yai or venturing into water adventures. Afternoons are best spent in the shade or relax in the resorts with the evenings a great time for catching a movie or shopping. You can also join a Thai cooking class or treat yourself with various massages and spas.

Koh Samui in September

September, the vacationing crowd retreats, making Koh Samui again quiet and less abuzz with people. The monsoons are still about a month away and the sunny days are best spent on the beaches or exploring the various local and tourist aspects of the island. Temperatures do not rise above 31 degrees with average rainfall at around 190mm. Unwind in the resort or vacation home during the rains or head out when the sun is bright, September is when the island is tranquil and at peace.

Koh Samui in October

October is when the retreating monsoons set in. The month may start on a sunny note, but heavy showers are expected towards the end of October. From mid-October, the tropical cyclones start making way in the warm seas around Thailand. The rains may be a heavy downpour or a continuous drizzle for a few hours. In spite of the showers, there are around five to six hours of sunshine to catch some outdoor fun. October also means celebrating Halloween in the many beach hotels revelling in the spooky fun.

Koh Samui in November

Officially called the winter month, November is still relatively warm compared to other countries of the world. The temperatures do not fall below 24 degrees, but plenty of rains and cyclone are expected. November is usually the wettest month of the offseason with rainfall around 300mm or more. The month preceding Christmas opens up great opportunities for shopping on the island which sees a drop in its tourism. The Loy Krathong Festival is a magical festival during the full moon night in November. Lanterns are floated in the sky, traditional krathongs and other small offerings are made as a symbolic manifestation of letting go off negative feelings.

Koh Samui in December

With temperatures still ranging from 25-27 degrees, December marks a relative fall in rainfall as the monsoons start subsiding. With Christmas and New Year Eve the beach and parties liven up, and the festivity rings through the atmosphere of the island. Early December is when the peak season is still a few weeks away, and tariffs are not too high as well.

Koh Samui Photos

Koh Samui, Thailand
Lipa Noi Beach at Sunset, Koh Samui
Golden Statue Of Buddha, Wat Phra Yai
Ang Thong National Marine Park - Established in 1980

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