Sintra weather by month
Sintra runs from about 11°C in December to 20°C in August, with March the wettest month at 181 mm.
warmest month
August
20°C
coolest month
December
11°C
wettest month
March
181 mm
worst air month
August
9 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 13°C | 157 mm | 217 h | 6 |
| February | 13°C | 123 mm | 235 h | 7 |
| March | 13°C | 181 mm | 274 h | 8 |
| April | 15°C | 46 mm | 333 h | 8 |
| May | 16°C | 21 mm | 380 h | 7 |
| June | 18°C | 72 mm | 337 h | 6 |
| July | 20°C | 7 mm | 383 h | 7 |
| August | 20°C | 1 mm | 354 h | 9 |
| September | 19°C | 19 mm | 317 h | 6 |
| October | 17°C | 152 mm | 250 h | 7 |
| November | 15°C | 84 mm | 227 h | 6 |
| December | 11°C | 12 mm | 261 h | 8 |
About 3,568 hours of sun a year. Roughly 87 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 2026-05-25. Full method, licences and the list of sources we rejected are on the methodology page.