2026 Climate Averages

Weather: San Sebastián — September

The weather is near-perfect with ideal temperatures and minimal rain. Recommended month to visit.

🌟 Climate Overview

September is an excellent time to visit San Sebastián. Warm weather with highs of 23°C—great for outdoor activities. This is one of the wettest months—waterproof gear is essential. As peak season, expect higher prices and more tourists. Sea temperature of 22°C is refreshing but swimmable.

5.7
GoTripzi Score Good

Based on weather comfort, crowds, prices, and activity options

Avg High

23°C

Avg Low

17°C

Rainy days

15days

Daylight

12.6h

Feels like 25°C / 17°C — humidity makes it feel warmer

Rainfall

135mm

Sunshine

9.3h/day

Humidity

79%

Humid
Sun Strength

5.8

High
Wind

17 km/h (gusts 35)

Sea Temp

22°C 💧 Refreshing

Is September a good time to visit San Sebastián?

The weather is near-perfect with ideal temperatures and minimal rain.

Now

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Feels like --
Wind --
Humidity --
UV Index --
Local time

Air Quality

Travel Context

  • Crowds
    Very Busy
  • Travel Costs Peak Rates

Daylight

Sunrise

07:47

Sunset

20:22

12.6h daylight

Visiting San Sebastián in September: Pros & Cons

Pros

  • Comfortable temperatures for sightseeing
  • Abundant sunshine for beach and outdoor fun
  • One of the best months to visit

Cons

  • Frequent rain may disrupt outdoor activities
  • Peak season — expect crowds and higher prices

Things to Do in September

Events & Festivals

🎭
Euskal Jaiak (Basque Festival Week)
First week of September Cultural
🎭
San Sebastián International Film Festival (Zinemaldia)
Late September (9 days) Cultural

Recommended for This Weather

🏛️ Museums & galleries
🍳 Cooking classes & food tours
🎭 Cultural tours & local experiences

San Sebastián Weather by Month

Month Avg High Avg Low Rain Sunshine Humidity UV Index Crowds Condition
Jan 13°C 8°C 15d (137mm) 5.8h
79% Humid
2.3 Moderate
Wet
Feb 15°C 9°C 12d (92mm) 7.2h
77% Humid
3.6 Moderate
Good
Mar 15°C 10°C 17d (120mm) 8.6h
75% Humid
5.2 High
Wet
Apr 17°C 11°C 14d (99mm) 9.6h
77% Humid
6.9 High
Wet
May 20°C 14°C 16d (103mm) 10.9h
80% Very Humid
8.1 Very High
Excellent
Jun 23°C 17°C 17d (131mm) 10.4h
83% Very Humid
8 Very High
Excellent
Jul 24°C 18°C 12d (52mm) 11.4h
82% Very Humid
8.4 Very High
Excellent
Aug 25°C 19°C 13d (98mm) 10.6h
82% Very Humid
7.5 Very High
Excellent
Sep Current 23°C 17°C 15d (135mm) 9.3h
79% Humid
5.8 High
Excellent
Oct 21°C 15°C 13d (135mm) 7.6h
78% Humid
4.1 Moderate
Wet
Nov 16°C 12°C 15d (173mm) 6.1h
80% Very Humid
2.5 Moderate
Wet
Dec 14°C 10°C 18d (183mm) 5.4h
81% Very Humid
2 Low
Wet

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Your Best MonthOctScore: 8

Where to Stay

See hotels, apartments & rentals around San Sebastián – live prices from Booking.com, Expedia, Vrbo and more

San Sebastián

Basque culinary capital, including La Concha beach, La Concha beach promenade and Pintxos bar hopping in Parte Vieja, pintxos bars, and Michelin-starred dining.

View Full Destination Guide

What to Pack for September

Summer clothing like shorts, t-shirts, and sundresses will be comfortable. Bring a light cardigan for air-conditioned spaces. A waterproof jacket and shoes are non-negotiable — showers are frequent.

Moderate Very Busy

🎒Personalized Packing List

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Your Packing List

📋Essentials
👕Clothing
👟Footwear
🎒Accessories
🧴Toiletries & Health

Planning a trip to San Sebastián?

🔥 Peak season — book early for best rates

Frequently Asked Questions

Is September a good time to visit San Sebastián?
September is typically excellent for visiting San Sebastián, with average highs of 23°C and around 15 rainy days. Plan your activities accordingly—outdoor sightseeing is best on dry days, while rainy days are perfect for museums and indoor attractions.
Does it get cold at night in San Sebastián in September?
Evenings in San Sebastián during September are mild at 17°C. A light cardigan or long sleeves for evenings is usually enough. Outdoor dining remains comfortable, making it a great time to enjoy rooftop bars and terrace restaurants.
What should I pack for San Sebastián in September?
With highs of 23°C and lows of 17°C in September, we recommend: Compact umbrella, Waterproof jacket/shell, Water-resistant shoes, Sunscreen SPF 30+. Layering is key as temperatures can vary between air-conditioned interiors and outdoors. Comfortable walking shoes are essential for cobblestone streets.
Does it rain a lot in San Sebastián in September?
San Sebastián typically sees around 15 rainy days in September. Rain is usually in the form of brief showers rather than all-day downpours, so a compact umbrella is sufficient. Mornings tend to be drier, making them ideal for outdoor sightseeing.
Can you swim in San Sebastián in September?
September is suitable for swimming in San Sebastián, though the water may feel refreshing at first. Air temperatures average 23°C, and most swimmers find it enjoyable once they're in. Midday is usually the warmest time for a dip.
How many hours of daylight are there in San Sebastián in September?
In September, San Sebastián gets approximately 12.6 hours of daylight per day. This affects how much sightseeing you can fit in—longer days mean more time for outdoor activities, while shorter days are perfect for cozy museum visits and early dinners.
Is September peak season in San Sebastián?
Yes, September is peak season in San Sebastián. Expect higher prices for accommodation and more crowds at popular attractions, but also the best weather conditions. Book hotels and major attractions in advance to secure availability and better rates.

Weather Data: Based on 2020–2025 historical climate data from Open-Meteo

Solar calculations: SunCalc (timezone: Europe/Madrid)

Last Updated: February 2026