San Sebastian weather in September 2025

The weather in San Sebastian in September 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 September 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 September 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.

Temperatures

25° / 23°

Rainy Days

Snowy Days

Dry Days

Rainfall

Sun Hours

11.9

Hrs

Sun	Mon	Tue	Wed	Thu	Fri	Sat
	1 24° /20°	2 24° /22°	3 24° /22°	4 23° /21°	5 23° /21°	6 23° /21°
7 24° /21°	8 25° /23°	9 25° /23°	10 25° /23°	11 24° /22°	12 24° /22°	13 24° /21°
14 24° /22°	15 24° /22°	16 25° /21°	17 24° /22°	18 23° /22°	19 24° /22°	20 24° /20°
21 24° /22°	22 24° /22°	23 24° /22°	24 23° /21°	25 24° /22°	26 24° /23°	27 23° /21°
28 24° /21°	29 24° /22°	30 24° /22°

Explore the weather in San Sebastian in other months

San Sebastian annual weather

Month	Temperatures	Rainy Days	Dry Days	Rainfall	Weather	More details
January	20° / 18°	1	30	16 mm	Good	San Sebastian in January
February	19° / 18°	1	27	17 mm	Good	San Sebastian in February
March	19° / 18°	0	31	9 mm	Good	San Sebastian in March
April	20° / 18°	0	30	8 mm	Good	San Sebastian in April
May	21° / 19°	0	31	1 mm	Good	San Sebastian in May
June	22° / 21°	0	30	1 mm	Good	San Sebastian in June
July	24° / 22°	0	31	0 mm	Perfect	San Sebastian in July
August	25° / 23°	0	31	5 mm	Perfect	San Sebastian in August
September	25° / 23°	0	30	7 mm	Perfect	San Sebastian in September
October	24° / 23°	1	30	22 mm	Perfect	San Sebastian in October
November	22° / 21°	1	29	25 mm	Good	San Sebastian in November
December	21° / 20°	1	30	23 mm	Good	San Sebastian in December