Weather and Seasons in Bangkok

wat_phra_kaew_and_grand_palace
Beautiful, clear blue skies over the Grand Palace

Stepping out of the air-conditioned confines of Bangkok’s Suvarnabhumi Airport and into the hot, humid air of Bangkok can be a shock to the system of a visitor unaccustomed to the weather of a tropical country. The weather in Bangkok is undoubtedly hot and humid; however, temperatures differ according to the time of year and even when temperatures are at their highest, taking some simple precautions can ensure that you are able to fully enjoy what this remarkable city has to offer.

 
Cool season in Bangkok (December to February)

The cool season sees the highest number of visitors arriving for a holiday in Bangkok owing to the more comfortable weather. Temperatures during this season average about 26°C/80°F.

Numerous outdoor beer and restaurant gardens pop up throughout the city during this time, giving everyone a chance to enjoy the breezy evenings that the cooler weather in Bangkok brings.

The temperature variation in Bangkok isn’t as marked as other more northern parts of Thailand and for those unused to tropical weather; even a midday cool season temperature may appear sweltering. It does get cooler at night, but this season is blessed with wonderful blue, cloudless skies for several months and lower humidity. Only a light jacket is needed in the evening.

 
Hot season in Bangkok (March to May)

Temperatures during this season can soar to a blazing 40°C/105°F! Add to that the congestion of urban Bangkok and the heat can be truly stifling. Such temperatures can be a health risk for some and simply energy-sapping for the rest – there is no rain to cool things off, other than the occasional unseasonal shower. Be sure to carry plenty of water and sun cream. If you’re not worried about such things and are willing to brave the discomfort of the heat and humidity, you will be rewarded with shorter queues as well as off-season discounts on hotels and travel.

 
Rainy season in Bangkok (May until November)

The rainy season is characterised by frequent torrential downpours and in Bangkok this can mean the flooding of many streets and areas close to the river. Despite the frequency of the rains, it tends not to last too long and have a welcome cooling off effect on the weather in Bangkok. The rainy season still produces plenty of hot, sunny days where the temperature is often well over 30°C/85°F and made worse by 90 per cent humidity. Showers can occur at any time of the day but usually arrive in the late afternoon as convection builds up. The wettest months are usually July and September, when there can be continuous cloud cover.

 
Weather in Bangkok by Month
 
January:

The weather is at its best in January in Bangkok. It cools down to the mid 20s (°C) during the northern winter, which reduces humidity and makes Bangkok a pleasant place to visit. It never rains, and it is one of the most popular months for tourists to hit the city, making it high season for hotel room rates. The good thing is that a day spent sightseeing won’t be sweaty and uncomfortable.

February:

It’s still fairly pleasant and relatively cool in Bangkok in February because the weather remains dry and cooler through to the end of the cool season. The humidity remains low, there’s rarely any rain and the tourist crowds are still at their height, so book your hotels early.

March:

From March the hot weather returns to Bangkok and any hint of ‘winter weather’ has passed as the midday temperatures reach the 30s (Celsius). However, it’s dry and because the rainy monsoons are still two months away the humidity is still bearable. There are still quite a lot of tourists passing through en-route to the islands from winter at home.

April:

Bangkok weather in April can become unbearably hot and it’s best to avoid the city at this time. It’s dry, the temperatures can top 40 and, apart from the Songkran water festival, there’s little reason to visit at this time. The traffic is better, though, because families clear out of the capital during the school holidays.

May:

By May, the chances of afternoon showers begins, but it remains very hot with humidity creeping in. Your sightseeing probably isn’t going to get spoilt by rainy weather but you will want to avoid being out during the middle of the day when temperatures can be unbearable for those unaccustomed to tropical heat.

June:

From June onwards Bangkok weather gets wet as the monsoon arrives; with it comes humidity which can reach 90 per cent or more. However, the tourist crowds have departed and although Bangkok tourist areas can be relatively busy all year round, you’ll find better rates on hotel rooms and tourist services.

July:

July is considered low season for Thailand’s tourism and this includes Bangkok, but the weather can still be reliable, if a little sticky. Expect humidity to be heavy and to be hanging in the air from the moment you step out of the airport. Frequent showers that can play havoc with traffic. It’s worth noting, though, that cloud cover can cool the harshness of the sun and it doesn’t rain endlessly.

August:

August weather in Bangkok is typified by regular showers and humidity, but areas like Khao San Road continue to attract backpackers during university breaks. However, most hotels offer low season rates, and places like Sukhumwit Road are less crowded.

September:

September in Bangkok can be one of the wettest months as the monsoon reaches its peak. This means lots of showers, but there are bouts of sunshine, too, alongside unpleasant humidity. Things cool off shortly after a shower but you soon find yourself soaked by sweat and dashing for air-conditioned shopping centres.

October:

The weather in Bangkok in October can be some of the most hazardous for its residents because there is often a triple whammy of floods from the north that burst the banks of the Chao Praya River, sometimes at the same time the tides are high and, if Bangkok is really unlucky, the remains of a Pacific cyclone dissipates in the region. All of these elements can lead to flooded streets, which often creates traffic havoc. But, mostly, visitors find tourist services to be less crowded and the skies sunny as the rainy season comes to an end.

Hot weather warning!
Bangkok is one of the hottest cities of its size in the world, but don’t worry, it’s also one of the most air-conditioned. Even in the cooler end-of-year months it might seem overly hot or humid relative to a cool European or North American climate, and those unaccustomed to the tropics need to take care to not get dehydrated or sunburnt. If you’re going to be out sightseeing, sunscreen should be used and plenty of liquids consumed. Rehydration salts (available widely) are a good remedy if you’re feeling flat, cramped or dizzy.

November:

Bangkok experiences pleasant weather in November as the rainy season subsides, the temperatures cool off and the humidity becomes barely noticeable. Tourist crowds are yet to arrive in full but many hotels put up room rates from 1st November. This is one of the most recommended times to visit Bangkok.

December:

December is the most popular time to visit Bangkok and the weather is often at its best. Night-time temperatures can be in the low 20s and you can spend the whole day out and about sightseeing without much risk of sunburn. The humidity disappears, the skies have no cloud and you’ll have plenty of other tourists for company.

 
Further reading…