Bangkok has a tropical monsoon climate, classified as Am in the Köppen system. The warmest month is May with an average high of 32°C, while the coldest month is January with lows dropping to 21°C. The annual temperature range of 11°C indicates a relatively stable climate year-round.
The driest month is December with only 6 rain days and 70mm of precipitation. For travellers, December through to the following month typically offers the best balance of warm temperatures and dry conditions. Average humidity ranges from 82% to 82% throughout the year.
Best Time to Visit Bangkok
Based on temperature and rainfall data, the best months to visit Bangkok are January, November, December. These months offer the most comfortable temperatures with relatively low rainfall, ideal for sightseeing and outdoor activities.
In May, Bangkok experiences average highs of 32°C (90°F) and lows of 25°C (77°F). Expect around 17 rainy days and 7 hours of sunshine per day, with humidity averaging 82%. The 7°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 8, so sun protection is advisable on clear days.
Bangkok typically sees 17 rainy days in May, with total precipitation of around 201mm. This is a notably wet period. A waterproof jacket or compact umbrella is essential, and it is worth building indoor alternatives into your daily itinerary for the inevitable rainy stretches. For context, the driest month in Bangkok typically sees 4-6 fewer rain days than May.
Pack lightweight, breathable clothing (linen or cotton), a wide-brim sun hat, SPF 50+ sunscreen, and a refillable water bottle for Bangkok in May. The 32°C daytime heat demands sun protection during midday hours, typically 11am to 4pm. A compact travel umbrella is also worth packing, as 17 rainy days means afternoon showers are a real possibility. Quick-dry synthetic fabrics are preferable to cotton in 82% humidity.
May can be a challenging time to visit Bangkok due to heavy rainfall across 17 days of the month. Indoor attractions, cultural sites, and covered markets are the strongest options this month. If your dates are flexible, the drier or milder months offer significantly easier travel conditions.
The average high temperature in Bangkok in May is 32°C (90°F), and the average low is 25°C (77°F). The mean daily temperature is approximately 29°C (83°F). The day-to-night range of 7°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Bangkok is generally February. February offers the most sunshine at 3 hours per day and only 9 rainy days. Average temperatures reach 29°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around February gives you the best chance of dry, bright weather.
May is shoulder or low season in Bangkok, meaning fewer tourists and generally lower prices than peak months. With 7 sunshine hours and 17 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In May, Bangkok suits a range of activities thanks to warm temperatures of 32°C. With frequent rain, indoor activities and covered attractions are a smart choice. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 7 hours of sunshine, parks and waterfront walks are particularly enjoyable.