The best months to visit Bilbao are May, June, September and October, when average highs sit in the comfortable low-20s and rain eases off. June reaches an average high of 23.2 °C with 12 rain days, while September brings 24.1 °C and 12 rain days — warm, bright conditions ideal for pairing the Guggenheim with riverside walks. July and August are Bilbao's peak season, with school-holiday crowds and busier streets. Winter is the quiet, low season: mild but wet, with January seeing 16 rain days and just 5.3 hours of sunshine a day.
Best months MayJuneSeptemberOctober
Bilbao month by month
Average highs and lows (°C), 2016–2025. Highlighted bars are the best months.
| Month | High | Low | Rain days | Sun / day |
|---|---|---|---|---|
| January | 12.5 °C | 5.7 °C | 16 | 5.3 h |
| February | 14.6 °C | 6.5 °C | 13 | 6.6 h |
| March | 15.7 °C | 7.4 °C | 17 | 8.1 h |
| April | 17.6 °C | 8.9 °C | 14 | 9 h |
| May | 20.1 °C | 11.3 °C | 14 | 10.2 h |
| June | 23.2 °C | 15 °C | 12 | 9.9 h |
| July | 24.9 °C | 16.7 °C | 10 | 10.8 h |
| August | 26 °C | 17.1 °C | 9 | 10.4 h |
| September | 24.1 °C | 15 °C | 12 | 9.6 h |
| October | 21.4 °C | 12.8 °C | 13 | 7.4 h |
| November | 16 °C | 9.2 °C | 17 | 6 h |
| December | 14 °C | 7.5 °C | 15 | 5.3 h |
How the months are picked.A month qualifies when its average high sits in the comfortable 20–28 °C band (scored down towards 9 °C and 37 °C), rain days are few and sunshine hours are high — at least 78 % of the city's best-scoring month. July and August are then set aside as peak season (school-holiday crowds and prices) whenever at least three other months qualify; where summer is the only comfortable window they stay. Figures are ten-year averages (2016-01-01 to 2025-12-31) from ERA5 reanalysis data via Open-Meteo (CC BY 4.0) for the city centre coordinates.
When to go, and what to expect
Spring (Mar–May)
May is a standout for mild warmth and long daylight; earlier spring stays showery.
Summer (Jun–Aug)
June is the sweet spot before the holiday rush; July–August suit those who want heat and don't mind crowds.
Autumn (Sep–Nov)
September and October are excellent — warm, less crowded; November turns wet and grey.
Winter (Dec–Feb)
For low-key city breaks and museums; expect frequent rain and short days.
Notable events
- August
- Aste Nagusia (Semana Grande) — Bilbao's biggest festival with fireworks, music and street parties
- July
- Bilbao BBK Live music festival
- December
- Santo Tomás fair — traditional market before Christmas
- March or April
- Semana Santa (Holy Week) processions
Frequently asked
Is August too hot in Bilbao?
Not extreme — August averages a high of 26 °C, the warmest month, with the fewest rain days at 9 and 10.4 hours of sunshine a day. It's comfortable but it's also peak season, so expect crowds.
What is the rainiest month in Bilbao?
March and November tie for the most rain, each with 17 rain days. January is close behind at 16. Bilbao is wet year-round, so even summer sees showers.
Is winter worth visiting Bilbao?
It's the quiet, low season and stays mild — January highs reach 12.5 °C — but it's wet, with 16 rain days and only 5.3 hours of sunshine a day. Good for museums and calm streets, less so for outdoor time.
Know when to go? Now decide where to stay — our Bilbao area guide →
Areas of Bilbao
Best time to visit near here
Sources
- Open-Meteo historical weather API — monthly climate normals, 2016–2025 (CC BY 4.0)
- ERA5 reanalysis (ECMWF / Copernicus) — the underlying temperature, precipitation and sunshine data
- ReasonStay methodology — how the best months are computed and checked
An independent guide to Bilbao — honest, verified, no invented data. Climate figures: ERA5 via Open-Meteo, 2016–2025 averages; the best months are computed from them, not opinion.