Bangkok (Krung Thep) — sää kuukausittain

According to the World Meteorological Organization, Bangkok is the world's hottest city. Just 14 degrees north of the equator, Bangkok is sunny at all times of the year with temperatures over 32°C. The most pleasant time to visit is the cool season that lasts from Nov-Feb. It is both the coolest and driest period — the Emerald Buddha statue in Wat Phra Kaeo even wears a scarf during this period! Don't think that's necessary though — daytime temperatures still hover around 32°C, but it does cool down to around 23°C, and on rare occasions can even dip as low as 15°C. March and April represent the hot season, and hot it is — 35°C on average. Average heat indices are around 42°C during the day and 30°C at night, but don't be surprised to see heat indices rising to 48°C or higher, with nighttime heat indices around 36°C. This is the worst season to visit Bangkok, so plan in a lot of air-conditioned shopping mall visits and get a hotel with a swimming pool.…

Bangkok forum threads consistently rate January as the best weather month of the year here - the least hot stretch, with humidity at its lowest and reliably dry conditions, typical lows around 20-21C and highs around 32-33C. Posters mentioned that occasional short cool spells can push down from China in December and January, sometimes dropping daytime temperatures below 20C for a couple of days before it warms back up. Because the weather is so favorable, threads were equally consistent on the tradeoff: this is peak high season, with hotel prices up and popular spots more crowded and fully booked than the rest of the year.

February is the cool season and by temperature the most pleasant stretch of the Bangkok year - 34C by day is still 38C to walk in, but nights fall to 25C and rain has stopped at 23.5mm across 4.3 days. The board's warning is about the same weather from the other side: the cool dry months from December to February are when a temperature inversion sits over the city and holds the traffic and construction dust down, which is why our AQI reads 125 now. They separate it from the northern smoke season, which is a March forest-burning problem rather than this one, and they say early February usually beats late February. The record: humidity 69 percent, 10.7 hours of sun and a 13.1 kph wind.

March is the hottest month here - 35.1C reading as 40C at 71 percent humidity, with nights that hold 26.9C - and it sits inside the season travellers know as the burning months. Regulars draw a distinction worth carrying: the crop and forest burning that ruins March in the north is a northern problem, while this city's haze is traffic, construction and industry, and it is there all year. Our column supports them: AQI 109 now against 101 in November and 154 in January, so the worst air here belongs to the cool season, not the burning one. Rain is not yet a factor at 37.4mm across 5.5 days. The record: 10.8 hours of sun and a 15.2 kph wind.

Bangkok-forum regulars are close to unanimous about April: it is the month they avoid. One writes that April is definitely their least favourite month to visit, "too damn hot", another lists March through May as brutally hot, and the standing recommendation is mid-October through December, when the weather settles and the crowds thin. Songkran splits opinion - regulars point out you can stay dry by avoiding the bar districts and the moat, while others simply leave town for the week. April's record: 36.2C days, 27.6C nights, humidity around 71 percent, nine precipitation days and 10.8 hours of sun, with AQI near 109.

Bangkok forum regulars call June rainy but not a washout: “it usually rains about one hour a day...but it usually doesn't rain everyday,” with mornings often fine and sunny and showers — sometimes spectacular thunderstorms — arriving in the evening instead. The heat is the part that wears people down more than the rain: “not oppressively hot but still hot and humid nationwide,” and one visitor who stayed three weeks called the combination “evil” by the end. The practical upside regulars point to: hotel rates drop for the June-July stretch. Our record: 32.8°C days, 75.4% humidity and rain on 20 of 30 days — genuinely wet, more days than not, backing the “doesn't rain every day but comes close” read more than the more optimistic forum takes.

Regulars split the month cleanly: early November still carries occasional late-afternoon showers lasting about an hour, hot but not oppressive, while mid-November marks the real start of the cool season, with nights capable of dropping to the low 20s or even high teens Celsius even as daytime highs stay well over 30C. Our row backs that transition, 33.3C reading as a hot 38C, over 25.3C nights, with 69.2mm of rain across 10.1 days. Regulars call this an excellent overall window - the wet season essentially over, crowds not yet built to peak-season size - with the back half of the month the more reliably dry and comfortable half to target. The record: humidity 74 percent, 9.2 hours of sun, an 11.7 kph wind and AQI 101.

December is the cool dry season, and 'cool' means 31°C with 60% humidity instead of 35 and 80. It's a real difference — you can walk the old city at midday. Air quality dips in the still weeks; the score's AQI here is worth reading.