Thailand’s tropical climate offers three seasons throughout the year, a rainy or southwest monsoon season from mid-May to mid-October, winter, or northeast monsoon season from mid-October until mid-February, and the summer season from mid-February until mid-May. Continue reading to learn more about the monsoon seasons, Thailand weather throughout the year, and the best time to visit Thailand.
When is Monsoon Season in Thailand?
When many of us think of a monsoon, we conjure up visions of heavy downpours, thunderstorms, and hurricane like weather, but that’s only the half of it. A monsoon is a seasonal shift in wind direction over a particular region that may include periods of heavy rainfall or a dry interlude.
In Thailand, there are only three months of the year that Thailand isn’t in monsoon season, from mid-February to mid- May. This is known as the transition time between the monsoons. Despite there being nine months out of the year of monsoon seasons, visitors are able to enjoy Thailand throughout the year.
The Southwest monsoon season begins in mid-May and lasts through mid-October. The Southwest monsoon brings warm moist air from across the Indian ocean creating heavy rain around Thailand with the locations around the Andaman Sea in the south, such as Phuket and Krabi, receiving the most impact.
The Northeast monsoon starts around October and ends in mid- February. The Northeast monsoon brings the cold and extremely dry air from China’s mainland to the upper north regions of Thailand and produces milder weather and an increase in rain for Thailand’s southeast coast where Chanthaburi, Pattaya, and Trat are located.
Summer or pre-monsoon season which begins mid-February and ends mid-May, brings warmer weather throughout Thailand, especially in the more tropical inland areas in the central and northern regions. Temperatures peak in April, which is considered the hottest month of the year with temperatures rising to 104° F (40° C) or higher. The coastal areas, which are cooled down by the sea breeze, get a little more relief with temperatures ranging from 91°-98°F (32.7° -36.6°C).
Weather by the Month
January: A great time to visit Thailand. Average temperatures in the south hover around 91° F (32.7°C) and range from 68°- 75°F (20°-24°C) in the northern parts of the country where it is generally cool and dry in January. The east coast islands in the Gulf coast, such as Koh Samui and Koh Pha Ngan typically continue to experience light rains throughout the month, averaging temperatures between 78°-84°F (26°-29°C).
February: Starts to see an increase in temperatures in central and southern Thailand, averaging 92°F (33.3°C). Northern Thailand continues to enjoy the dry and cooler climate with clear skies and temperatures between 71°-77°F (22°-25°C) making this region a nice respite from the hotter south. This is a great time to visit Khao Sok National Park when this rainforest is at its warmest and driest. And most excitingly, the world’s largest flower, the Rafflesia, blooms in February within the Khao Sok National Park.
March: The heat gets turned up in March, with temperatures in the north rising to 95°F (35°C) and ranging between 77°-88°F (26°-31°C) in the southern regions with lots of blue skies and plenty of sunshine. Koh Samui and the east Gulf coast islands are a bit cooler than their southern counterparts. Temperatures also rise in central Thailand, as does the humidity, and this region can experience brief downpours throughout the day.
April: Oppressive. In addition to the humidity, the high temperatures can make it difficult to get much site sightseeing in. This is a good time to head to the east coast of Thailand’s Gulf where the temperature’s a bit cooler ranging between 84°- 93°F (29°-34°C).
May: Temperatures begin to drop across the country and rainfall and humidity increases in most regions. This is a good time to visit the east or west coast of the Gulf of Thailand where this region experiences little rain compared to the other beaches and islands in southern Thailand. This is a good time to visit if you don’t mind some showers throughout the day and want to visit when there are less tourists.
June: Temperatures across the country remain in the mid to high 80°s F (29°-31°C) with short down spurts of heavy rain throughout most of the month. In the north, the heavy rainfall results in muddy trails which lend to the not best hiking. Despite the short down spurts of rain, most areas will have warm and sunny skies throughout the day. The Gulf is great to visit this time of year, not only are there less visitors, but sunshine is a high probability on these beaches as well as those on the islands of Koh Pha Ngan and Koh Samui.
July: Temperatures continue to drop with most of the country experiencing heavy rainfall and temperatures in the low to mid 80s°F (29 C). The sea becomes rougher making most of the tourist water activities unsafe. The east coast of the Gulf of Thailand comes to the rescue again in July. For those travelers seeking drier sunny beach days, Koh Samui, Koh Pha Ngan, and Koh Tao are the places to visit in July.
August: Heavy rain continues across most of the country in August. Travelling can be difficult in the north due to mud slides and flooding. Temperatures continue to slightly drop, and the humidity remains high. As is in April- July, the east coast of the Gulf of Thailand continues to have drier weather through the month.
September: Humidity reaches its peak in September as rainfall and frequent thunderstorms are common throughout most of the country. Temperatures drop, averaging between 77°-48°F (25°- 9°C) in the north and 77°F (25°C) in the south. Khao Sok National Park is at its wettest in September but is a good time to view wildlife with the appropriate attire.
October: Rains continue around the country, but winter is right around the corner with less rain and sunny skies on the way. Of course, the weather is unpredictable, and the wet season does last through November at times.
November: In general, rain subsides, sunny skies prevail, and humidity remains low. This is another great month for outdoor enthusiasts to visit the northern regions where the weather is dry and sunny most days and the temperature remains cool. It can get chilly in the evening, so a light sweater or jacket is recommended. The south of Thailand begins to experience dryer days with an average temperature of 82°F (28°C) making this a great time to Krabi and Phuket. September is not the time to visit the east coast of the Gulf, as this is the wettest month in and around Koh Samui and Koh Pha Ngan.
December: Other than the huge influx of tourists visiting, December has the best weather throughout the country. Bangkok and central Thailand averages in the high 70°F (26°C) and maintains low humidity making it an ideal time for sightseeing. The same is true for the northern regions though it is a bit cooler, between the low to high 70°F. Southern Thailand is a bit warmer than the rest of the country sitting in the mid to high 80°F (31°C) making this a great place to visit for water sports and lounging on the beach.
Weather Highlights by Region
North and Northeast Thailand
- Best time to visit: December through February
- Worst time to visit: July through August
- Slash and burn farming practices begin in January which produces a lot of smoke congestion from March through July.
Central Thailand
- Best time to visit: November through February
- Worst time to visit: April through May (hottest), September through October (wettest).
- December and January: Coolest and driest months
- May through September: wettest months
Gulf Coast
- Best time to visit the west coast: April through June
- Best time to visit the east coast: March through August
- September: wettest month on the east coast
South Thailand
- Best time to visit: November through February
- Worst time to visit: May through October
- April and May, and September through October are the hottest months.
- September and October: wettest months.
Tourist Season
The cool dry season, beginning in November and extending to early March, is the best time to visit central and southern Thailand. This is also a popular time for backpackers to visit the northern regions. Northern Thailand experiences colder months in December and January (68°F- 20°C) with a cool breeze in the morning and evenings and mostly clear skies. It is not as hot or humid as other seasons and more suitable for hiking.
The low tourist season is between mid-May and mid-October when the country experiences high humidity with lots of rain, although June tends to have a few weeks without rainfall.
High tourist season is mid- October through mid-February when travelers will have the least chances of rain with less heat and humidity.
Conclusion
As you see, anytime of the year is the best time of year to visit Thailand. No matter what time of the year or which monsoon season Thailand is experiencing, there are great opportunities for visiting year-round. Even in the rainy seasons, the rain generally doesn’t last all day and is often in the morning and night. The weather is unpredictable so it’s always a good idea to look at the local weather forecast when planning your trip, and pack accordingly!
Thanks for reading, come back soon for more adventures. And as always, I invite you to reach out if you have any questions or just want to share ideas, or your travel stories.
Feel free to email me at cyanne@bestdestinationsthailand.com or leave a comment below. Together, we can share our experiences or just learn from others. The world opens to those with knowledge.
All the best,
Cyanne