Rainy Season in Thailand A Complete Month-by-Month Guide for Families

Thinking about travelling to Thailand but worried about the weather? The words “rainy season in Thailand” might trigger visions of endless downpours and flooded footpaths, but the reality is far more nuanced and often, much more beautiful. With regional variations, bursts of sunshine between showers, and lush landscapes, understanding Thailand’s monsoon season can actually help you plan a better, cheaper and less crowded holiday especially if you’re travelling as a family.

In this post, I’m breaking down the rainy season across every major region and province in Thailand, giving you the inside scoop on when to go, where to avoid, and why the monsoon months might just be the hidden gem of Southeast Asian travel.

Affiliate Disclaimer: This post may contain affiliate links. If you purchase through them, I may earn a small commission at no extra cost to you. Thank you for supporting our family travels!

What Is the Rainy Season in Thailand?

The rainy season in Thailand is driven by the southwest monsoon winds, which sweep across the country from around May to October. This seasonal shift brings a noticeable increase in humidity and rainfall but let’s bust a big myth straight away: it doesn’t rain all day, every day. Far from it!

In fact, most places across Thailand still enjoy plenty of sunshine during the rainy season, especially in the mornings. What you’ll often get are short, intense downpours usually in the late afternoon or evening that last anywhere from 30 minutes to a couple of hours. Think dramatic tropical storms, big thunderclaps, and a proper soaking… then it’s done. Streets dry quickly, the air feels fresher, and life carries on as normal.

It’s actually a great time to travel if you’re prepared. The rain keeps everything lush and green, especially in the mountains and rice fields, and with fewer tourists around, you’ll find a more relaxed vibe and lower prices on everything from hotels to tours. For families, this means more room to explore, better deals, and less stress trying to squeeze into packed attractions.

So yes; it’s wetter, sure. But a total washout? Absolutely not. The Thailand monsoon season has its own rhythm, and once you understand it, you can easily plan around it and make the most of your time here.

When Is the Rainiest Month in Thailand?

If you’re googling “rainiest month Thailand,” the answer is usually September across most provinces, this is when the downpours peak. Whether you’re in Bangkok, Chiang Mai or Krabi, September is statistically the wettest. If you’re a sunshine chaser, that’s the one month to approach with caution.

Rainy Season Thailand: Region-by-Region Breakdown

Rainy season in Thailand isn’t the same everywhere. Different parts of the country get hit at different times and some spots stay dry while others are drenched.

Central Thailand

Key locations: Bangkok, Ayutthaya, Kanchanaburi

Rainy season: May to October
Rainiest months: August & September
Good to know: Bangkok can flood quickly but usually recovers within hours. Plenty of indoor attractions make it a solid option year-round.

Northern Thailand

Key locations: Chiang Mai, Chiang Rai, Pai

Rainy season: May to October
Rainiest month: September
Best for: Waterfalls, rice fields, nature lovers. Morning hikes and temple visits before the rain hits in the afternoon.

Eastern Thailand

Key locations: Pattaya, Koh Chang, Rayong

Rainy season: May to October
Rainiest months: August & September
Watch out for: Koh Chang is notoriously wet so much so that some resorts close during peak rainy season.

Northeastern Thailand (Isaan)

Key locations: Ubon Ratchathani, Khon Kaen, Nakhon Ratchasima

Rainy season: May to October
Rainiest month: September
Highlights: Authentic rural life, green rice paddies, and fewer tourists.

Southern Thailand: Two Coasts, Two Monsoons

This is where things get interesting the south of Thailand has two completely different rainy seasons, depending on which coast you’re on.

Andaman Coast

Key locations: Phuket, Krabi, Koh Lanta, Trang

Rainy season: May to October
Rainiest months: September & October
Expect: Choppy seas, boat trip cancellations, fewer crowds, lush rainforests
Best for: Budget-conscious families who don’t mind a bit of weather and want peaceful resorts

Gulf Coast

Key locations: Koh Samui, Koh Phangan, Koh Tao

Rainy season: October to December
Rainiest month: November
Fun fact: July and August are often sunny here while the Andaman side is soaked!
Perfect for: Families wanting beach time during UK summer holidays

Thailand Rainy Season by Province

Province	Rainy Season	Rainiest Month
Bangkok	May – Oct	September
Chiang Mai	May – Oct	September
Phuket	May – Oct	September
Krabi	May – Oct	September
Koh Samui	Oct – Dec	November
Koh Phangan	Oct – Dec	November
Koh Tao	Oct – Dec	November
Chiang Rai	May – Oct	September
Ubon Ratchathani	May – Oct	September
Pattaya	May – Oct	September
Koh Chang	May – Oct	August

Best Places to Visit During the Rainy Season in Thailand

If you’re visiting Thailand during monsoon season, here are some family-friendly destinations where the rain either won’t bother you or will actually make your trip more magical:

Koh Samui (June–August): Drier than the Andaman coast
Chiang Mai (May–July): Green landscapes and light rain
Bangkok (year-round): Endless indoor activities
Pai (June): Misty mornings, fewer crowds
Ayutthaya: Historical ruins that are even more atmospheric in the rain

Should Families Travel During the Rainy Season in Thailand?

Absolutely if you’re smart about it. Travelling to Thailand in the rainy season can be a brilliant decision, especially for budget-conscious families who don’t mind a little spontaneity.

Pros:

Lower prices on flights and accommodation
Fewer crowds at popular tourist spots
Cooler temperatures compared to April heatwaves
Green, vibrant landscapes — especially in the north

Cons:

Flash floods in urban areas (especially Bangkok)
Cancelled ferries and tours
Muddy treks in the north and east
Some island resorts may close during low season

What to Pack for Thailand’s Rainy Season

A few essentials will go a long way in keeping your family dry and happy:

Lightweight rain jackets or ponchos (for kids and grown-ups!)
Waterproof shoes or quick-dry sandals
Travel-size umbrella
Dry bags or ziplock pouches for phones, passports and electronics
Quick-drying clothes
Mosquito repellent

Shop My Travel Must Haves!

Rainy Season Thailand Travel Tips

Travelling during the rainy season in Thailand doesn’t mean your holiday is ruined it just means you need to be a little bit savvy with your planning. Here are some essential tips to help you make the most of your time, even when the skies open up!

1. Start your days early
Mornings in Thailand during the monsoon season are typically the driest part of the day. The sun is often shining, the streets are less crowded, and the air is fresher before the afternoon humidity builds. If you’re exploring temples, heading to a national park, or taking the kids to the beach, aim to get out early and enjoy those clear skies before the rain rolls in.

2. Stay informed about ferry and tour cancellations
In coastal areas and the Thai islands, weather-related disruptions can affect ferries, snorkelling trips, and island-hopping tours. Always double-check the forecast the night before and confirm bookings with local operators especially if you’re travelling between islands like Koh Samui, Koh Tao, or Phi Phi. Some ferries are cancelled not because of rain, but because of rough seas. Apps like 12Go Asia and websites like Thai Meteorological Department can help you stay updated.

3. Have backup indoor activities in mind
When the heavens open, it’s handy to have a Plan B. Think museums, indoor play centres, or cultural attractions with covered walkways. Places like SEA LIFE Bangkok, Chiang Mai’s Art in Paradise, or even just popping into a family-friendly café with a kids’ corner can save your afternoon. Many temples also have shaded or indoor areas, so you can still soak in some culture without getting drenched.

4. Don’t fully trust your weather app
Weather apps tend to show a thunderstorm icon every single day during the rainy season, which can feel a bit dramatic. The truth? Tropical storms in Thailand are super unpredictable. One minute it’s blue skies, the next it’s a full-on monsoon downpour and then it clears up like nothing happened. So don’t panic if your forecast looks stormy every day. Look for patterns, talk to locals, and stay flexible.

FAQ: Rainy Season in Thailand

1. Is it OK to visit Thailand in the rainy season?
Yes, absolutely! Visiting during the rainy season in Thailand has its perks. You’ll enjoy cheaper accommodation, fewer crowds, and lush, green landscapes that make everything feel alive and tropical. Just be mindful of the rainiest periods in certain provinces (more on that below), and plan a bit more flexibility into your days.

2. What’s the worst month for rain in Thailand?
Typically, September is considered the rainiest month in most of the country, especially in Bangkok, Chiang Mai, and the Andaman coast (think Krabi, Phuket). But here’s the twist the Gulf of Thailand, including Koh Samui, Koh Phangan, and Koh Tao, actually tends to stay relatively dry in September and gets its wettest weather a bit later in the year.

3. Which island is the wettest during the rainy season?
Koh Chang, located near the Cambodian border, sees some of the heaviest rainfall during the rainy season in Thailand. Trails through the jungle can get muddy and slippery, and ferry services are sometimes cancelled due to rough seas. It’s still beautiful, but definitely more rugged during monsoon months.

4. Is it dangerous to travel during the rainy season in Thailand?
Generally, no but some extra caution is smart. Roads can get slippery, especially on scooters. Mountain trails might become muddy or flooded, and sea conditions can be rough. Always check local advisories and don’t take unnecessary risks if a big storm is rolling in. Island-hopping? Always reconfirm ferry schedules in advance.

5. Will it rain all day every day?
Not usually. The rainy season in Thailand tends to bring short, heavy showers, most often in the late afternoon or evening. Mornings are usually clear, and some days it might not rain at all. You’ll still get plenty of sunshine between the storms.

6. Can I still go island hopping in the rainy season?
Yes, but it depends on where you are. The Andaman Coast (Phuket, Krabi, Koh Lanta) sees heavier rain between May and October, while the Gulf Coast (Koh Samui, Koh Phangan) stays relatively dry until October–December. Choose your region wisely depending on your travel dates.

7. Are national parks and waterfalls open in the rainy season?
Many national parks in Thailand are at their most stunning during the rainy season waterfalls are in full flow, and the landscapes are lush and green. But be aware: some parks or hiking trails might close temporarily due to landslides or safety concerns. Always check in with local guides or rangers before setting off.

8. Is it a good time to visit Thailand with kids?
Totally! With a bit of flexibility, visiting during the rainy season in Thailand with kids can be a great adventure. There are plenty of indoor attractions, family-friendly hotels often offer lower rates, and you won’t be battling the peak-season crowds. Just pack rain gear, plan early starts, and keep a list of rainy-day backups on hand.

9. Do flights and transport get affected by the rainy season?
Domestic flights rarely get cancelled due to rain alone, but ferries and longtail boats can be delayed or called off during big storms or rough seas. In rural areas, roads might flood temporarily. Always give yourself a bit of buffer time when moving between locations during the Thailand rainy season.

10. What should I pack for travelling during the rainy season in Thailand?
Essentials include: a lightweight rain jacket or poncho, quick-dry clothing, waterproof shoes or sandals, a dry bag for electronics, and a few plastic zip bags for snacks and documents. Don’t forget bug spray the rain brings the mozzies out in full force!