Het weer in Kanchanaburi (River Kwai) in maart

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.

Kanchanaburi's forum makes a genuine case for June despite it being rainy season: multiple posters said it's actually a favorite time to visit specifically because the countryside turns lush and green without the seasonal haze that dulls the dry months. The rain pattern is an hour or so of showers that cools things down, then the rest of the day is fine - not the all-day washout the 'rainy season' label suggests. Hot and humid is still the baseline, the rain is more relief than obstacle.

Forum posters describe December days here as warm enough to relax by the pool, with cooler mornings typically warming up comfortably by afternoon. This tracks the broader central-Thailand pattern posters describe for the month: hot, sunny days around 32C, clear skies and minimal rain, with evening temperatures dipping into the low-20s or even high-teensC for a genuinely comfortable night. Posters recommend Kanchanaburi's surrounding national parks and dams as worthwhile day-trip additions to the town's famous WWII-era sites, with December's dry, clear conditions well suited to the outdoor sightseeing involved.