Bangkok weather by month: temperatures, rainfall and rainy days

Wat Arun from the Chao Phraya River under a cloudy sky Photo above: Manit Monsur via Google

Bangkok weather is hot in every month: the average daily high ranges from 32.3°C (90°F) in December to 35.7°C (96°F) in April, according to the 1991–2020 climate normals for the Thai Meteorological Department's Bangkok Metropolis station. What changes through the year is the rain. December to February are the driest months, with about one or two rainy days each, while September is the wettest, with 336 mm of rain on 18 days. For most visitors, November to February is the most comfortable stretch, and January is one of the driest and least humid months of the year.

What is the weather in Bangkok each month?

The table below shows Bangkok's weather by month as long-term averages for 1991 to 2020. Highs and lows are the average daily maximum and minimum temperatures. Rainy days are days with at least 1 mm of rain. These are climate normals, not a forecast: any single year can run hotter, wetter or drier.

Over a whole year, Bangkok averages about 1,700 mm (67 in) of rain on roughly 105 rainy days. Nights stay warm all year: the lowest monthly average minimum is 23.2°C (74°F), in December.

What is the weather like in Bangkok in January?

The weather in Bangkok in January is warm, dry and sunny. The average temperature in Bangkok in January runs from a low of 23.4°C (74°F) to a high of 32.7°C (91°F). January averages 24 mm of rain on about two days, 216 hours of sunshine and 68% relative humidity, so most days are dry and the air feels less heavy than in the rainy months.

Mornings are the pleasant part of a January day, and they are the time for outdoor sights. Walk or cycle in Lumphini Park or Benjakitti Park before the heat builds, or cross the river early to Wat Arun. Afternoons still reach the low 30s°C, so plan shade and water. January is also peak travel season, so book hotels early; our guide to things to do in Bangkok in January has ideas for the month.

What is the cool season in Bangkok like (November to February)?

Bangkok's cool season runs roughly from November to February. It is cool only by Bangkok's standards: average highs stay between 32°C and 34°C (90°F to 93°F), but nights drop to about 23°C to 25°C and humidity is at its lowest, around 66% to 71%. Rain is rare, with one to four rainy days a month.

That makes it the season most visitors aim for; our guide to the best time to visit Bangkok weighs the weather against crowds, festivals and prices.

The Tourism Authority of Thailand describes this part of the year as three months of dry, cooling breezes, and it is when the city is busiest with visitors. December is the driest month of all, with 12 mm of rain on about one day; see things to do in Bangkok in December.

How hot is Bangkok in the hot season (March to May)?

March to May is Bangkok's hot season, and April is the hottest month, with an average high of 35.7°C (96°F) and an average low of 27.2°C (81°F). March and April are still mostly dry, with three to five rainy days, but storms become more frequent and May is already one of the wetter months.

In the hot months, do outdoor sightseeing early and move indoors at midday. Air-conditioned options include the Bangkok Art and Culture Centre, the National Museum Bangkok and the malls around Siam, such as Siam Paragon. Songkran, the Thai New Year, falls in mid-April. For March ideas, see things to do in Bangkok in March.

When is the rainy season in Bangkok?

The rainy season in Bangkok runs roughly from May to October. May to August bring 190 mm to 227 mm of rain a month on 12 to 16 days, and the rain peaks in September (336 mm on 18 days) and October (289 mm on 14 days). Even in September, about 12 days of the month on average stay dry, with less than 1 mm of rain.

The UK Foreign Office also describes Thailand's rainy season as generally May to October and warns that weather has become less predictable, with intense downpours possible. Heavy rain can flood streets and slow road traffic badly. On September 26, 2026, for example, the Tourism Authority of Thailand advised visitors that rainfall and localized flooding in parts of Bangkok could delay road and rail journeys, including trips to the airports, and suggested the BTS Skytrain and MRT as alternatives to the roads. Our guide to when rainy season is in Bangkok covers planning in more detail, and why Bangkok floods and sinks explains the geography behind it.

For individual months, see our guides to Bangkok in June, July, August, September and October.

Which month has the best weather in Bangkok?

On the long-term averages, December and January have the best weather in Bangkok for sightseeing: they are the coolest months, with average lows of about 23°C (74°F), the lowest humidity and only one or two rainy days. November and February are close behind. April is the hottest month and September the wettest.

Rain does not make the wet season a write-off. Temperatures are a little lower than in April, and the city's museums, malls and covered markets work in any weather. A river trip is still possible in the dry hours between showers, and you can use the BTS and MRT when streets flood.

What should you wear for Bangkok's weather?

Light, breathable clothing works in every month, with a compact umbrella or rain jacket from May to October. Temples need more cover: the Grand Palace and the major temples expect covered shoulders and knees, so carry a light layer that meets the rule. Our guide to what to wear in Bangkok goes season by season.

Where can you check Bangkok's weather forecast?

The Thai Meteorological Department publishes daily and seven-day forecasts at tmd.go.th and runs a weather hotline on 1182. In the rainy season, also check the Tourism Authority of Thailand's travel updates before heading to the airport, and allow extra time on the roads after heavy rain. The UK Foreign Office notes that Bangkok can also have high air pollution at times, so check an air-quality index if you have asthma or a similar condition.

Sources: WMO Climate Normals 1991–2020, Bangkok Metropolis station 48455 (Thai Meteorological Department data, published by NOAA NCEI), Thai Meteorological Department, Tourism Authority of Thailand visitor information, September 26, 2026, Tourism Authority of Thailand on Thailand's climate, UK Foreign Office travel advice for Thailand. Checked September 26, 2026.