Ayutthaya weather by month
Ayutthaya runs from about 27°C in December to 33°C in April, with September the wettest month at 332 mm.
warmest month
April
33°C
coolest month
December
27°C
wettest month
September
332 mm
worst air month
March
42 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 28°C | 6 mm | 318 h | 36 |
| February | 29°C | 8 mm | 307 h | 42 |
| March | 30°C | 37 mm | 327 h | 42 |
| April | 33°C | 6 mm | 352 h | 36 |
| May | 30°C | 303 mm | 292 h | 31 |
| June | 29°C | 283 mm | 284 h | 19 |
| July | 28°C | 269 mm | 199 h | 16 |
| August | 28°C | 300 mm | 278 h | 15 |
| September | 28°C | 332 mm | 247 h | 18 |
| October | 28°C | 248 mm | 317 h | 19 |
| November | 28°C | 39 mm | 318 h | 20 |
| December | 27°C | 0 mm | 318 h | 17 |
About 3,557 hours of sun a year. Roughly 181 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-24. Full method, licences and the list of sources we rejected are on the methodology page.