Thailand Weather

"When to go"

Thailand has a tropical and humid climate throughout the year!

But many backpackers prefer to travel during the cool season because they love the mix of sunny Thailand weather, and the refreshing cooler climate.

The year in Thailand can roughly be divided into three seasons: cool season (Nov-February), hot season (March-May) and wet season (June-Oct).

In general:

Even it`s called the wet season, it doesn`t rain for a long period in Thailand. There`s usually short rain showers followed by sunshine. And if you want cheap accommodation in Thailand, travelling during the wet season is the ideal time of year.

And the same applies for the cool/hot season…

Even if you`re travelling during the cool/hot season, you have to expect some rain in most parts of the country. It`s not guaranteed that it won`t rain.

Note: The temperatures mentioned below are average monthly daytime temperatures.

Source: worldweather.org

Bangkok

Bangkok is like any city in Southeast Asia: hot and humid through out the year! The temperature can rise up to 36 Celsius. During the wet season it will usually rain in the afternoon, and some days it will rain all day.

Nov to Feb: Min 21 ºC, Max 33 ºC
March to May: Min 24 ºC, Max 36 ºC
May to Oct: Min 24 ºC, Max 34 ºC
Heaviest rainfall: September and October

Here`s the weather forecast for Bangkok -- updated by Thai meteorological Department.

Chiang Mai

There`s of course tropical climate in Chiang Mai, but it`s cooler and less humid than other parts in Thailand. The temperature will drop at nights (even in the cool season in Dec and Jan), so you should bring a sweater.

Nov to Feb: Min 14 ºC, Max 32 ºC
March to May: Min 19 ºC, Max 36 ºC
May to Oct: Min 22 ºC, Max 34 ºC
Heaviest rainfall: August and September

Here`s the weather forecast for Chiang Mai -- updated by Thai meteorological Department.

Now we have reached Southern Thailand. Southern Thailand has only two seasons: wet and dry.

Eastern Coast (Gulf of Thailand)

Koh Tao, Koh Pha Ngan, Koh Samui

During the cool/hot season, the days on the islands are mostly sunny, but you`ll occasionally feel the strong breeze/wind. The average temperature all-year is about 30 ºC!

The period between September to November is known as the wet season. You`ll experience rain showers once in a while, but only for a couple of hours.

We stayed on Koh Pha Ngan mid-December for 10 days. 6 of 10 days were overcastted followed by sunshine, but it was still hot during daytime. You`ll notice that the weather here is pretty much unpredictable (as rest of Thailand).

Dec to Feb: Min 24 ºC, Max 29 ºC
March to August: Min 25 ºC, Max 33-35 ºC
September to Nov: Min 24 ºC, Max 31 ºC
Heaviest rainfall: Sep/Oct - Dec

Best time to snorkel/dive (as in best visibility):

March - October

During this period there are few currents and the visibility can be 20 meters! March, April and May are considered as the best months for diving because of the combination of water clarity and guaranteed sunshine!

Average water temperature: 30 ºC

Here`s the weather forecast for Koh Samui -- updated by Thai meteorological Department.

Koh Chang

After the monsoon months, you`ll likely experience cooler nights in November and December on Koh Chang. March to April are the hottest months. If you`re planning on staying a lot in the water, you can probably handle these months.

From May to October it rains a lot. But don`t get me wrong… it doesn`t rain constantly. There has actually been sunny days during the wet season.

Nov to April: Min 20 ºC, Max 35 ºC
Mid-May to Oct: Min 24 ºC, Max 32 ºC
Heaviest rainfall: August

Best time to dive (as in best visibility):

Oct/Nov - May

The water visibility is variable and depends on where on the island you`re heading. But the water clarity can reach 25-30 meters!

Average water temperature: 28 ºC - 30 ºC

Weather forecast for Trat (Koh Chang is located outside Trat) -- updated by the Thai Meteorological Department.

Western Coast (Andaman Sea)

Krabi, Koh Phi Phi

From December to April you`ll likely experience sun and blue skies. But there can be rain in the earlier months of the cool/dry season (Nov/Dec) because of the transition from the wet season. Otherwise the Thailand weather from Nov to Jan is mostly clear blue skies, some breeze and cool nights.

And if you can handle the hot and dry climate, the hottest months are March and April where the temperature range from 30-36.

When I was in Phi Phi in late December, 6 of 7 days were sunny. Some days started with overcastted sky, then the scorching sun appeared around noon. The 7th day was overcastted and there was a short rainshower in the afternoon.

Nov to April: Min 20 ºC, Max 36 ºC
May to Oct: Min 18 ºC, Max 30 ºC
Heaviest rainfall: October
Even if the period between May to Oct is called the wet season, there`s more sun than rain.
Usually the rain will come in the evening. And during daytime there`s a change of sun and cloudy skies. But it`s still very hot during October, and the rainfall can cool you down.

Best time to snorkel/dive (as in best visibility):

February - May

The water is at its warmest and clearest during this time. Water visibility depends on which island you`re going to. Average water clarity is between
5-20 meters.

Average water temperature: 25-30 ºC

I can tell you that when we snorkelled by Maya Beach in Mid-December, the currents were still strong but managable.

Here`s the weather forecast for Krabi -- updated by the Thai Meteorological Department.

Note: Notice that the two monsoons are affecting the west and east coast of Thailand differently.

Picture it this way: If it`s less rain on the Eastern coast, it rains more on the Western coast! Ying and Yang!

So, what conclusions can we draw from this?

If travelling during the cool season, the weather is "perfect": a combination of sunny days + cooler nights.
The downside is that you will encounter thousands of tourists during this period. It is the most popular time to travel to Thailand.
If you`re a sun-lover and can handle the hot Thailand weather, head for Thailand during the hot season. And you`ll likely share the beach with fewer people. Best of all, you will get a great snorkelling/diving experience because of the good water clarity and calm seas.
But remember to drink lots of water. You are losing water even if you`re not noticing it!
The downside is that the Thailand weather during this time is HOT HOT! If you`re staying a long time in Thailand, you might feel that you had enough of the sun!
To read more about sun safety, go here!
If you`re on a tight budget and want cheap accommodation, you should consider travelling during the wet season. The prices for accommodation are 30-50 % cheaper than during the cool/hot season!
But if you go diving, the water clarity is not at its best. And you have to accept the fact that it will rain.

You`re done with Thailand Weather, where do you want to go next?
Back to About Thailand?

Leave Thailand Weather and Return to Backpacking Tips Asia Homepage.