Thailand Weather in December 2025: Travel Tips for First Visitors

The weather in Thailand in December is cool and dry, offering a respite from the warmth of previous months. The average daily maximum temperature hovers around 32°C (89°F), while the average daily minimum temperature is a comfortable 24°C (75°F).

In December, one of the most prominent events that you can't miss is the Chiang Mai CAD New Year Countdown Event. This event offers the opportunity to witness thousands of lanterns and fireworks illuminating the night sky in a breathtaking spectacle. To ensure a smooth and hassle-free visit, join our New Year countdown tour where we handle all the arrangements, allowing you to fully immerse yourself in the wonder of this incredible celebration.

Thailand Weather in December: Overview

• Average temperature range: 24–32°C (75–89°F)
• Rainfall: 12 mm (0.5 inches)
• Rainy days: 6
• Sunny days: 15

The Regional Weather in Thailand in December

Weather in Northern Thailand (Chiang Mai, Chiang Rai...)

In December, the northern regions of Thailand, including Chiang Mai and Chiang Rai, experience a pleasant and cool climate. The temperatures typically range from 15 to 25°C (59 to 77°F), providing a refreshing break from the hotter months. Temperatures typically drop to around 15°C (59°F) at night and in some years the temperature has been as low as 12°C (54°F). 

So remember to bring a few pieces of warm clothing, such as a jacket or jeans. 

The cooler weather is perfect for exploring the mountainous landscapes, lush greenery, and cultural treasures that abound in this part of the country.

Weather in Central Thailand (Bangkok, Ayutthaya...)

The central regions, including Bangkok and Ayutthaya, experience mild and comfortable temperatures during December. Daytime temperatures hover around 25 to 30°C (77 to 86°F), and there is typically just 1 day of low rainfall, around 2mm (0.08 inches) in December. It is pleasant to do sightseeing and outdoor activities.

Weather in Southern Thailand (Phuket, Krabi, Koh Samui...)

The southern regions, encompassing popular destinations like Phuket, Krabi, and Koh Samui, boast a warm and tropical climate in December. With temperatures ranging from 25 to 32°C (77 to 90°F), this is the perfect time to enjoy the stunning beaches, crystal-clear waters, and vibrant marine life that characterize the region.

However, the weather differs between the east coast (Koh Samui and Koh Phangan) and the west coast (Phuket, Krabi, and Koh Phi Phi).

At the beginning of December, places like Phuket, Ko Lanta, and Ko Phi Phi on the west experience dry conditions and warm sea temperatures. On the other hand, Koh Samui still sees some rain, wrapping up the monsoon season. But towards the end of December, both Koh Samui and Koh Phangan enjoy more sunny days, making it a great time to visit.

Insider tip: Thailand's neighborhood countries Vietnam and Cambodia also have comfortable weather in December. For your 2-week Christmas holiday, visiting these three countries in one trip would be a smart choice as well.

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Best Places to Visit in Thailand in December

December is one of the best months to travel to Thailand. The weather of December is hot/warm in the south and mild/cool in the north, and the monsoon rains cease in most of the country. Here are some of the best-recommended places to visit in December.

1. Bangkok

The vibrant capital city of Thailand, Bangkok, is a year-round destination, but December offers cooler temperatures, making it more comfortable for sightseeing. Explore the Grand Palace, visit bustling markets, and experience the city's lively nightlife. The cooler evenings also make it an ideal time to take a leisurely boat ride along the Chao Phraya River, admiring the city's illuminated skyline.

Additionally, the festive decorations and events during the Christmas and New Year season add to the city's charm. 

If you're in Bangkok for New Year's Eve, join the festivities at CentralWorld, where a massive countdown event takes place with live music, fireworks, and a lively crowd. It's a memorable way to ring in the new year in the heart of the city.

Check the sample itineraries for Thailand tours: 10 days, 14 days, and 21 days >>>

2. Chiang Mai 

In Chiang Mai, if you are planning to celebrate Christmas and New Year, we highly recommend participating in the Chiang Mai CAD Countdown Event, where thousands of lanterns and fireworks are released to create a once-in-a-lifetime experience. 

For more activities in Chiang Mai, consider exploring the Old City and its historic temples, such as Wat Phra Singh and Wat Chedi Luang. Another option is to visit Doi Suthep, a mountain overlooking Chiang Mai, where you can explore the magnificent Wat Phra That Doi Suthep. Additionally, take advantage of the pleasant weather by participating in a Thai cooking class.

Get more ideas on Chiang Mai weather in December or planning a family trip to Thailand.

3. Ayutthaya

The weather in Ayutthaya in December is pleasantly warm with a gentle breeze. It is comfortable to explore this once-thriving ancient city and visit the ancient temples of Ayutthaya.

Caring for rescued elephants and biking through the old French, Portuguese, British, and Dutch quarters are some of the recommended activities.

4. Khao Yai National Park

December is a great time to explore Khao Yai National Park's jungle (a UNESCO World Heritage site). You can take a half-day or day-long tour to explore caves, spot a lot of birds, see elephants (and other wild animals), and enjoy waterfalls.

Camping in the park on New Year's Eve with the starry sky might be a special gift for your family.

5. Phuket 

December marks the beginning of the dry season on the west coast, including Phuket. With clear skies and warm temperatures, this popular island destination is ideal for enjoying its beautiful beaches, vibrant nightlife, and water activities. Explore the Old Town, relax on Patong Beach, or take boat trips to nearby islands.

6. Koh Samui

Despite some lingering rainfall at the beginning of December, Koh Samui in the Gulf of Thailand is a tropical paradise worth visiting. As the month progresses, the weather becomes more favorable, making it an excellent time to relax on the stunning beaches, explore the island's natural beauty, and participate in water activities.

Koh Samui usually has smaller crowds due to its higher airfare and fewer flights and higher price of accommodation. 

Insider tip: For your first trip to Southeast Asia, you can also consider exploring Thailand, Vietnam, and Cambodia together in one trip as they're conveniently connected and share a similar climate. You could also see December weather in other Southeast Asian countries>>>

December Crowding and Costs

December is the peak travel season in Thailand, especially during the "Western" holiday season (the Christmas / New Year's break). The tourist areas can be extremely crowded, and hotel and flight costs are much higher than in other months. So, book early (2-3 months in advance) to save more.

Check some Thailand tours for inspiration.

What to Wear in December?

The lowest temperature in December is about 24°C (76°F) in most of Thailand. So, shorts, skirts, light trousers, T-shirts, and other light clothes are good for this month. Bring a few pieces of warm clothing, such as a jacket or jeans, if you go to northern Thailand, which can sometimes get below 15°C (70°F).

Monthly Weather and Travel Information for Thailand

Learn about the weather in Thailand for 12 months and find out the best places to visit each month.