Climate averages 1991–2020

Donostia / San Sebastián weather
by month.

See how the year changes. August has the highest average daily maximum; July has the lowest average monthly rainfall.

Long-term climate patterns, not a forecast for a particular trip.

Warmest month 23.3°C August, average high
Coolest month 6.3°C February, average low
Wettest month 170 mm November, monthly total
Driest month 82 mm July, monthly total
The year at a glance · average highYear overview

Across the year Donostia / San Sebastián averages a daytime high of 16.8°C and a nighttime low of 11.4°C, with about 1,412 mm of rain on roughly 171 days. August is the warmest month (average high 23.3°C) and January the coolest (11.2°C). November is the wettest month with 170 mm; July is the driest with 82 mm.

The annual picture

A year in Donostia / San Sebastián

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. 051015202530 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 2000

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Donostia / San Sebastián climate table

1991–2020
Monthly climate averages for Donostia / San Sebastián, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January 11.2°C6.5°C6.5°C13515.49.49 h
February 11.6°C6.3°C6.3°C12314.110.510 h
March 13.7°C7.8°C7.8°C11413.911.912 h
April 15.1°C9.2°C9.2°C12716.113.413 h
May 18.0°C12.0°C12.0°C11715.414.715 h
June 20.6°C14.7°C14.7°C9312.715.315 h
July 22.4°C16.7°C16.7°C8212.615.115 h
August 23.3°C17.4°C17.4°C8912.914.014 h
September 21.4°C15.6°C15.6°C9612.912.513 h
October 18.8°C13.3°C13.3°C12814.311.111 h
November 14.2°C9.6°C9.6°C17015.79.810 h
December 11.9°C7.5°C7.5°C13815.19.09 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

Nearby cities

Distance from Donostia / San Sebastián

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits
What do the high and low temperatures mean?

We average the daily maximum and daily minimum for each calendar month over 1991–2020. They are not record extremes, a forecast range or temperatures at a fixed time of day.

How is a rain day counted?

A local calendar day (standard time, UTC+1, no daylight saving) with at least 1 mm of total precipitation counts as one rain day. We count these for each year and month, then average across 30 years. The average does not predict which days will be wet.

Where do the numbers come from?

ERA5-Land (temperature) and ERA5 (precipitation) reanalysis from the Copernicus Climate Change Service, read from the Open-Meteo open-data archive. Temperature comes from the 0.1° model cell at 43.30°, -2.00° (3 km from the city centre), adjusted up by 0.7°C for the difference between the city's elevation (17 m) and the cell's (123 m). Rain comes from the 0.25° cell at 43.25°, -2.00°. These are model estimates, not weather-station readings; coast, hills and city streets can differ.

Does this page show sunshine, humidity or sea temperature?

No. The data used here contain air temperature and precipitation only. Daylight hours are calculated from the city's latitude (sunrise to sunset), not measured sunshine.