Month by month
| Month | Afternoon | Sea | Rain | Verdict |
|---|---|---|---|---|
| January | 11.8 °C | 12.7 °C | 16 days | Unfavourable season |
| February | 13.5 °C | 12.5 °C | 15 days | Possible, with trade-offs |
| March | 14.9 °C | 12.8 °C | 17 days | Possible, with trade-offs |
| April | 16.7 °C | 14.1 °C | 14 days | Possible, with trade-offs |
| May | 19 °C | 16.4 °C | 16 days | Possible, with trade-offs |
| June | 21.9 °C | 20 °C | 14 days | Possible, with trade-offs |
| July | 23.7 °C | 22.1 °C | 12 days | Pleasant — a good time to go |
| August | 24.4 °C | 22.7 °C | 12 days | Pleasant — a good time to go |
| September | 22.7 °C | 21.5 °C | 13 days | Pleasant — a good time to go |
| October | 20.3 °C | 18.7 °C | 13 days | Pleasant — a good time to go |
| November | 15.7 °C | 16.2 °C | 17 days | Possible, with trade-offs |
| December | 13.9 °C | 14.2 °C | 14 days | Possible, with trade-offs |
Before you go
Three things to check once you have picked your dates.
Entry
Spain is in the European Union. Entry rules depend on your nationality — check before booking.
Safety
No specific restrictions
Usual precautions apply.
Official advice updated 12 August 2026
Health
Recommended vaccinations, water quality, mosquitoes: advice depends on the country and the season. Some vaccines need time before departure.
Beau Fixe is not a safety or health authority. These notes summarise public advisories and link to their source; only the competent authorities are authoritative. Alert levels: Foreign, Commonwealth & Development Office (gov.uk), Open Government Licence v3.0.
FAQ
Can you swim in Donostia / San Sebastián in December?
The sea averages 14.2°C in December — too cold for most swimmers.
How hot is Donostia / San Sebastián in December?
Expect 13.9°C in the afternoon and 8.2°C at night, averaged over the last 10 years.
Does it rain a lot in Donostia / San Sebastián in December?
Around 14 days with rain (≥ 1 mm) in the month — 45% of days.