The weather in San Sebastian in August is very hot. The average temperatures are between 23°C and 25°C, drinking water regularly is advisable.
As it is almost never rain during August in San Sebastian the weather is perfect for hanging out outside and exploring all that San Sebastian has to offer.
Our weather forecast can give you a great sense of what weather to expect in San Sebastian in August 2025.
If you’re planning to visit San Sebastian in the near future, we highly recommend that you review the 14 day weather forecast for San Sebastian before you arrive.