Thailand weather in September

Wondering about the weather in Thailand in September? In this article we cover everything from average air and sea temperatures to what to look forward to on your Thailand vacation and what to expect.

Is September a good time to visit Thailand?

September can be a challenging time to visit Thailand as it falls during the rainy season. The weather in Thailand in September is characterised by frequent rainfall, high humidity and the possibility of tropical storms. Despite the lush and colorful scenery, outdoor activities may be limited and some islands and beaches can have rough seas. 

Travelers should also be prepared for occasional heavy rainfall and that accessibility to some tourist areas and activities may be reduced. It is advisable to check weather forecasts, plan flexible itineraries and keep an eye on local conditions. On the plus side, travelers looking for less crowded and budget-friendly vacation options can find good deals during this period.

Ready to explore Thailand? Embark on your dream trip hassle-free with the help of our Thailand travel experts.

Average daily temperatures in September

September is one of the wettest months in Thailand, particularly in the south. Bangkok experiences temperatures between 78°F (26°C) and 90°F (32°C) with about 12 inches (300mm) of rainfall. Chiang Mai remains cooler, with highs of 87°F (31°C) and lows of 72°F (22°C). 

Phuket, Krabi and Samui are drenched with up to 14 inches (360mm) of rain, but temperatures still range from 77°F (25°C) to 87°F (31°C). Sunshine is reduced to around 4-5 hours per day. 

September is ideal for those looking to avoid crowds and take advantage of lower prices, but be prepared for frequent rain. Inland regions like Chiang Rai and the Golden Triangle offer a cooler, less rainy alternative to the coast.

What about the crowd & cost?

September is one of the rainiest months in Thailand, especially along the Andaman Coast (Phuket, Krabi, Koh Phi Phi). This keeps tourist numbers low, and prices for accommodations and tours are at their lowest. While beach destinations may feel quiet, northern regions like Chiang Mai and Chiang Rai are still accessible and less affected by the rains. It’s a good time to explore cultural and historical sites if you don’t mind occasional downpours.

Rough Guides tip: Find even more ideas for your fall adventure with our guide to the best places to travel in September.

What to do in Thailand in September

While going on a trip, one must consider the weather in Thailand in September and the nuances that this month brings. You may also be interested in our list of the best things to do in Thailand at any time of year.

Go monsoon kayaking in Ao Thalane

In September, embark on a thrilling monsoon kayaking adventure at Ao Talan in Krabi. Soak up the rain as you paddle through enchanting mangrove forests and towering limestone cliffs. The rainy season offers a unique perspective as the landscape is adorned with lush greenery.

Explore Krabi Hot Springs and rainforest

Experience the natural wonders of Krabi in September with a visit to Klong Thom Hot Springs. Enjoy the therapeutic benefits of thermal pools surrounded by lush rainforests.

To find the ideal season to visit Thailand for you, make sure to read all about the best time to visit Thailand.

Go island-hopping in Koh Chang

Despite the rain, explore the lush landscapes and waterfalls of Koh Chang Island. Take advantage of the reduced number of tourists and enjoy the serene beauty of this tropical island.

Enjoy Thai cookery classes

Avoid the rainy weather by taking part in a Thai cooking class. Learn to prepare traditional dishes and learn Thai cooking techniques with a unique indoor class.

Visit traditional Thai retreat

Escape the rain by visiting a traditional Thai retreat center. Many resorts and spas offer wellness packages to relax and rejuvenate.

Ready to embark on a Thailand adventure? Don't miss our Thailand itineraries and information on how to get there. 

Festivals and events in Thailand in September

There are several festivals and events that take place in Thailand in September. Here's our pick:

• Vegetarian Festival (nationwide): Nine-day Taoist celebration observed widely, especially in areas with Chinese communities. Participants follow a strict vegetarian diet and wear white. Includes temple visits and merit-making activities.
• Moon Festival (Chinese community): Also known as the Mid-Fall Festival. Families gather to admire the full moon, eat mooncakes, and light lanterns. Particularly celebrated in areas with large Chinese populations.
• Hua Hin Food Festival: Culinary event showcasing local and international cuisine. Features food stalls, cooking demonstrations, and competitions. Promotes Hua Hin as a gastronomic destination and supports local food industry.

Plan your trip with our Thailand itineraries

Our Thailand itineraries are crafted to help you experience the best of the country, stress-free. Think of them as a starting point — perfect for planning, but flexible enough to adjust to your own pace and interests. After all, travel is about freedom, but a little planning goes a long way.

• Thailand itinerary 7 days: A week in Thailand is just enough to see the highlights, usually a mix of Bangkok, one cultural destination, and some beach time.
• Thailand itinerary 10 days: Ten days lets you explore multiple regions, such as Bangkok, northern Thailand, and a few days on the coast.
• Krabi itinerary: Explore Krabi’s famous limestone cliffs, emerald waters, and hidden beaches. Great for adventure enthusiasts with options for island hopping, rock climbing, and snorkeling.
• Phuket itinerary: A Phuket trip offers a mix of vibrant nightlife, beautiful beaches, and cultural sites. Expect lively markets, water activities, and a range of beach resorts.
• Chiang Mai itinerary: Discover Chiang Mai’s rich cultural heritage, from ancient temples to bustling night markets. Ideal for travelers looking for a blend of history, local crafts, and lush mountain scenery.