Donostia / San Sebastián, Spain Climate
The warmest month is August, with an average high of 24°C; the coldest is February, with an average low of 7°C. A normal year brings 1060 mm of precipitation.
Temperature through the year
The normal daily high and low. The line marks today.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
Normals for Sep 25
- Normal high
- 21°C
- Normal low
- 16°C
- Reanalysis high
- 26°Cin 2013
- Reanalysis low
- 10°Cin 2002
- Chance of a wet day
- 41%
- Daylight
- 12 h 02 min
Month by month
Averages for 1991-2020. Wet days have at least 1 mm of precipitation in the reanalysis. Each month links to its own page.
| Month | Avg high | Avg low | Warmest | Coldest | Precipitation | Wet days |
|---|---|---|---|---|---|---|
| January | 11°C | 7°C | 17°C (2001) | 0°C (2017) | 109 mm | 15.5 |
| February | 11°C | 7°C | 20°C (2019) | -2°C (2012) | 88 mm | 11.3 |
| March | 13°C | 9°C | 21°C (1997) | -1°C (2005) | 81 mm | 12.4 |
| April | 15°C | 10°C | 25°C (2005) | 3°C (1996) | 90 mm | 15.0 |
| May | 18°C | 13°C | 28°C (2005) | 7°C (2019) | 78 mm | 12.4 |
| June | 21°C | 16°C | 34°C (2003) | 10°C (2006) | 69 mm | 12.0 |
| July | 23°C | 18°C | 35°C (1995) | 13°C (1997) | 53 mm | 9.3 |
| August | 24°C | 18°C | 36°C (2003) | 14°C (1993) | 53 mm | 9.3 |
| September | 22°C | 17°C | 33°C (2016) | 10°C (2002) | 78 mm | 12.0 |
| October | 19°C | 14°C | 28°C (2001) | 5°C (2003) | 102 mm | 12.4 |
| November | 14°C | 11°C | 22°C (2015) | 3°C (2007) | 144 mm | 15.0 |
| December | 12°C | 8°C | 19°C (2000) | -2°C (2001) | 115 mm | 15.5 |
| Year | 17°C | 12°C | 1060 mm | 152 |
Precipitation
Rain and melted snow together. The chance of a wet day is the share of days with at least 1 mm of precipitation in the reanalysis.
1060 mm in a normal year, most in November.
Chance of a wet day
- Chance of a wet day
Humidity and comfort
NASA POWER reanalysis, 1991-2020, for the grid cell around Donostia / San Sebastián.
The muggiest month is August, when 16 percent of days are muggy or worse, with a mean dew point of 18°C or more.
| Month | Dew point | Humidity | Dry | Comfortable | Humid | Muggy | Oppressive | Miserable |
|---|---|---|---|---|---|---|---|---|
| January | 6°C | 82% | 100% | 0% | 0% | 0% | 0% | 0% |
| February | 6°C | 81% | 100% | 0% | 0% | 0% | 0% | 0% |
| March | 7°C | 80% | 100% | 0% | 0% | 0% | 0% | 0% |
| April | 9°C | 80% | 98% | 2% | 0% | 0% | 0% | 0% |
| May | 12°C | 80% | 68% | 28% | 3% | 0% | 0% | 0% |
| June | 14°C | 80% | 27% | 41% | 31% | 2% | 0% | 0% |
| July | 16°C | 79% | 6% | 32% | 48% | 14% | 0% | 0% |
| August | 16°C | 77% | 4% | 30% | 50% | 16% | 0% | 0% |
| September | 14°C | 76% | 25% | 41% | 30% | 4% | 0% | 0% |
| October | 12°C | 78% | 57% | 36% | 7% | 0% | 0% | 0% |
| November | 9°C | 81% | 94% | 6% | 0% | 0% | 0% | 0% |
| December | 7°C | 82% | 100% | 0% | 0% | 0% | 0% | 0% |
Comfort is judged by the day's mean dew point: dry below 13°C, comfortable to 16°C, humid to 18°C, muggy to 21°C, oppressive to 24°C, miserable above.
Clouds
Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.
The clearest month is September, with the sky 61 percent covered on average; the cloudiest is January, at 73 percent.
Wind
The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.
The windiest month is December, averaging 18.4 km/h at 10 meters (33 feet) above the ground.
Daylight and sunshine
The longest day is Jun 16, with 15 h 24 min of daylight; the shortest is Dec 18, with 8 h 58 min.
- Day length
Solar energy
Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.
Month pages
The weather in Donostia / San Sebastián in each month, day by day.
What this means
A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.
Where no station record is within reach, the extremes shown are the highest and lowest the reanalysis produced for the date in 1991-2020, not measured records.
Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.
More for this place
Nearby
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.