Bilbao weather by month
Bilbao runs from about 10°C in December to 21°C in August, with October the wettest month at 195 mm.
warmest month
August
21°C
coolest month
December
10°C
wettest month
October
195 mm
worst air month
March
11 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 10°C | 86 mm | 178 h | 7 |
| February | 11°C | 148 mm | 160 h | 8 |
| March | 12°C | 100 mm | 231 h | 11 |
| April | 13°C | 83 mm | 270 h | 11 |
| May | 15°C | 120 mm | 295 h | 8 |
| June | 18°C | 58 mm | 258 h | 9 |
| July | 21°C | 36 mm | 328 h | 7 |
| August | 21°C | 49 mm | 284 h | 10 |
| September | 17°C | 160 mm | 259 h | 7 |
| October | 17°C | 195 mm | 200 h | 8 |
| November | 14°C | 103 mm | 207 h | 6 |
| December | 10°C | 127 mm | 155 h | 10 |
About 2,825 hours of sun a year. Roughly 128 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 2026-05-23. Full method, licences and the list of sources we rejected are on the methodology page.