Weather in San Sebastián for September 2025
In general, the average temperature in San Sebastián at the beginning of September is 21.3 °C. As the month progressed, temperatures tended to slightly decrease, reaching an average of 21.1 °C by the end of September.
Expect significant rainfall in San Sebastián during September, with an average of 18 rainy days.
Is September a good time to visit San Sebastián? check out the best time to travel to San Sebastián page.
- New! Chat with our AI weatherman - it’s amazing and free.
San Sebastián in September average weather
Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
---|---|---|---|---|---|---|
1 22° | 2 19° | 3 20° | 4 22° | 5 21° | 6 22° | 7 23° |
8 23° | 9 23° | 10 21° | 11 21° | 12 18° | 13 18° | 14 21° |
15 22° | 16 22° | 17 21° | 18 21° | 19 21° | 20 22° | 21 20° |
22 16° | 23 19° | 24 20° | 25 24° | 26 21° | 27 19° | 28 19° |
29 22° | 30 23° |
You can click on date
Temperatures trend during September in San Sebastián
September weather day by day
Date | Weather | Temperatures | Rain | UV | More |
---|---|---|---|---|---|
1 Sept. | Cloudy | 22° /15° | 2.4 mm | 5 | |
2 Sept. | Moderate or heavy rain with thunder | 19° /15° | 14.4 mm | 5 | |
3 Sept. | Partly cloudy | 20° /15° | 2.9 mm | 5 | |
4 Sept. | Patchy rain possible | 22° /16° | 7.7 mm | 5 | |
5 Sept. | Sunny | 21° /15° | 8.2 mm | 6 | |
6 Sept. | Patchy rain possible | 22° /15° | 2.8 mm | 5 | |
7 Sept. | Partly cloudy | 23° /15° | 0.8 mm | 6 | |
8 Sept. | Partly cloudy | 23° /16° | 0.7 mm | 6 | |
9 Sept. | Patchy light rain with thunder | 23° /15° | 2.4 mm | 5 | |
10 Sept. | Patchy rain possible | 21° /15° | 2.2 mm | 5 | |
11 Sept. | Patchy light rain with thunder | 21° /15° | 2.4 mm | 5 | |
12 Sept. | Moderate or heavy rain shower | 18° /14° | 12.7 mm | 4 | |
13 Sept. | Partly cloudy | 18° /13° | 1 mm | 5 | |
14 Sept. | Partly cloudy | 21° /12° | 0 mm | 6 | |
15 Sept. | Thundery outbreaks possible | 22° /13° | 0 mm | 6 | |
16 Sept. | Patchy light drizzle | 22° /14° | 0.2 mm | 6 | |
17 Sept. | Partly cloudy | 21° /15° | 0.3 mm | 5 | |
18 Sept. | Patchy rain possible | 21° /14° | 0.8 mm | 6 | |
19 Sept. | Patchy rain possible | 21° /14° | 2 mm | 5 | |
20 Sept. | Sunny | 22° /14° | 3.2 mm | 6 | |
21 Sept. | Light rain shower | 20° /14° | 6.8 mm | 5 | |
22 Sept. | Light rain shower | 16° /13° | 5 mm | 4 | |
23 Sept. | Patchy rain possible | 19° /11° | 0.2 mm | 5 | |
24 Sept. | Sunny | 20° /13° | 0.9 mm | 5 | |
25 Sept. | Sunny | 24° /14° | 0.2 mm | 6 | |
26 Sept. | Patchy rain possible | 21° /15° | 12.3 mm | 5 | |
27 Sept. | Cloudy | 19° /13° | 3.1 mm | 5 | |
28 Sept. | Sunny | 19° /12° | 2.3 mm | 5 | |
29 Sept. | Patchy rain possible | 22° /14° | 0.1 mm | 6 | |
30 Sept. | Sunny | 23° /15° | 0 mm | 6 | |
Next |
San Sebastián in September - FAQ
What to pack to San Sebastián in September?
As you prepare for your trip to San Sebastián in September, it's important to consider the typical weather patterns for the time of year. Below is a carefully tailored packing list to ensure that your time in San Sebastián, during September, is comfortable and enjoyable, regardless of the weather conditions.
- Clothing
- Layered Clothing: Light sweaters, long-sleeve shirts, light jackets, and comfortable pants
- Rain Gear: Lightweight, waterproof clothing
- Footwear
- Waterproof Shoes
- Accessories
- Sunglasses: For sun protection
- Sun Hats: Wide-brimmed hats for sun protection in warm weather
- Umbrellas/Raincoats: For rainy days
September rainfall patterns in San Sebastián
UV exposure in San Sebastián during September
Quick links
Get accurate weather forecasts for San Sebastián, located at latitude 43.201 and longitude -4.423. Stay updated with localized weather information tailored for San Sebastián.