Mild
Average highs are around 23°C, so days are mild rather than hot.
September verdict
San Sebastian, Spain in September
Weather score52Mixed
Mixed for holiday weather
Average highs are around 23°C, so days are mild rather than hot. Sunshine averages 5.8h per day, enough for a balanced month. Rainfall averages 97mm, so some wet days are possible.
September weather
Monthly averages
Temp
23°C
Rain
97mm
Sun
5.8h
Sea
21°C
Weather score
52
Mixed
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 97mm, so some wet days are possible.
Some sun
Sunshine averages 5.8h per day, enough for a balanced month.
Cool sea
Sea temperatures average 21°C, so the water can feel cool.
Map
Weather map
Compare San Sebastian, Spain with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
September23°C average high
September is one of San Sebastian's warmest months, with daytime heat above the yearly average.
Warmest monthsJune to September
This stretch sets the upper range for average daytime heat.
Rain
September97mm average rain
September sits near San Sebastian's yearly rainfall average, so rain is a normal planning factor rather than an outlier.
Driest monthsJune to August
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
September5.8 hours average sun
September is brighter than San Sebastian's yearly average, though the strongest sunshine usually sits closer to the peak months.
Brightest monthsJune to August
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
September21°C average sea
September sits in the warmer sea-temperature season, usually making swimming easier to enjoy.
Warmest seaJuly to September
Sea temperatures are usually near 21°C in this stretch, so swimming comfort is at its strongest.
Weather score
September52 weather score
September scores above San Sebastian's yearly average, so the overall weather mix is stronger than most months.
Best weather monthsJune to September
These months have the strongest weather score in the monthly averages.
