August 17 is generally a great time to visit San Sebastian. While there is a slight chance of rain (31%), showers are usually brief. Expect comfortable 24°C weather. As it's peak season for San Sebastian, we recommend booking your stay well in advance to secure the best rates.
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Essential Travel Info for San Sebastian
Currency
EUR
€ Euro
Language
Spanish
+3 more
Driving
Right side
Safety
High Safety
GPI: 1.603
San Sebastian Weather Forecast for August 17
"Mild & Comfortable. Expect average highs of 23.7°C. 31% chance of rain."
What to Wear in San Sebastian in August
Based on historical data for August 17, San Sebastian typically experiences temperatures between 17.3°C and 23.7°C. We recommend packing t-shirt, light clothing, umbrella to stay comfortable. With a 31% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for San Sebastian
Smart Suitcase
- T-Shirt
- Light Clothing
- Umbrella
Average High
23.7°C
Daytime Peak
Average Low
17.3°C
Nighttime Low
Feels Like
24.4°C
☀️ Feels accurate
Rain Chance
31%
Avg 1.6mm if it rains
Cloud Cover
58%
Light drizzle
Pressure
1017.2 hPa
Low volatility
San Sebastian Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 96% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
06:00 - 10:00
16:00 - 20:00
Type I-II
🔴 21 min to burn
Type III-IV
🟡 32 min to burn
Type V-VI
🟢 53 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
20.4°C
Humid/Sticky
Heat Stress
Low
No heat warning
🙂 Best outdoor time:
Any time during daylight hours
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
✅ Excellent Swimming Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Spain
Flight Traffic
High
87/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~26
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in San Sebastian
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:16
☀️ Noon
13:13
🌇 Sunset
20:10
⏱️ Daylight
13h 54m
Wind Speed
13.9 km/h
Gentle breeze
Sunshine
10.1 hrs
Direct Sun (Cloud-free)
Humidity
82%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for San Sebastian
Smart Flight Estimator
Airport-to-Airport Logistics
unlock smart flight estimates
Add your home location in settings to see airport details.
Travel Health & Safety in San Sebastian
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🔴 Very Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Stable conditions. Low risk of headaches.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Rare minor tremors. Buildings are earthquake-resistant.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, San Sebastian on August 17 averages 23.7°C with a 31% precipitation probability. Wedding/Outdoor Event Score: 95/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
San Sebastian Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
August 10
24.9°C • 20% rain
Score
99
August 11
24.8°C • 21% rain
Score
98
August 12
24.7°C • 21% rain
Score
98
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (August 17) in other destinations
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📍 Is San Sebastian Worth Visiting on August 17?
Planning a trip to San Sebastian on August 17? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 23.7°C with a 31% historical precipitation risk.
✈️ Travel Logistics: Approximately 26 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 7 vaccinations are recommended for Spain, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 23.5°C (swimming pool). Wave conditions are generally fun waves with heights around 0.96m.
📊 Historical Extremes: The hottest August 17 recorded in the last 30 years saw temperatures hit 28.2°C in 2025, while the coldest dropped to 15.3°C in 2022.