San Sebastian or Porto in August?
In August, San Sebastian and Porto are overall neck and neck — it comes down to your priorities.
San SebastianPhoto: Ander.gd · CC BY-SA 4.0
PortoPhoto: Ken & Nyetta · CC BY 2.0Key figures in August
| Criterion | San Sebastian | Porto |
|---|---|---|
| Average daily high | 24 °C | 25 °C |
| Average daily low | 19 °C | 17 °C |
| Sea | 22 °C ★ | 17 °C |
| Rainy days | 10 rainy days (est.) | 3 rainy days (est.) ★ |
| Sun | 7 h/day | 8 h/day ★ |
| Humidity | 77 % | 72 % |
Winner by travel type
Trade-offs
- Porto is drier, with about 6 fewer rainy days.
- The sea at San Sebastian is about 5 °C warmer.
San Sebastian or Porto in August: the short answer
In August, San Sebastian and Porto are essentially level on the overall climate score (both around 83/100). The decision comes down to the individual criteria below.
This comparison focuses on August as a representative month for the pair; for any other month, use each destination's month-by-month pages. Across the whole year San Sebastian averages a climate score of 50/100, Porto 57/100. Both profiles below are historical monthly averages, not a forecast.
Weather in August, side by side
The average daily high is about 24 °C in San Sebastian and 25 °C in Porto — warmer in Porto. Average daily lows are around 19 °C versus 17 °C.
On rain, San Sebastian sees about 10 rainy days in August and Porto about 3 — drier in Porto. Porto gets more sunshine (7 vs 8 hours a day).
Sea temperature and swimming
In August the water is about 22 °C at San Sebastian and 17 °C at Porto — warmer for swimming at San Sebastian. Over the year, San Sebastian is comfortable for swimming (from ~21 °C) in July and August, Porto in no month. Peak sea warmth is August for San Sebastian and September for Porto.
Rain and sun across the year
Over a full year San Sebastian records roughly 153 rainy days and Porto about 117 — the drier of the two overall is Porto. At their sunniest, San Sebastian reaches about 7 hours of sun a day (June) and Porto about 9 (July). If dependable dry, sunny weather is your top priority, weigh these annual totals alongside the single month above.
Best time to visit each
Climatically, San Sebastian is at its best in June, July, August and September, while Porto peaks in June, July, August and September. If your dates are fixed, pick the destination whose strong season overlaps them; if you are flexible, plan around these windows.
Which suits which kind of trip
Based on the August scores for each travel style:
Beach & swimming: San Sebastian scores higher in August (San Sebastian 82 vs Porto 76).
City breaks: Porto scores higher in August (San Sebastian 90 vs Porto 96).
Active & hiking: Porto scores higher in August (San Sebastian 76 vs Porto 85).
Family: San Sebastian scores higher in August (San Sebastian 83 vs Porto 80).
Verdict: which should you pick?
There is no single winner — it depends on your month and your priority. For August specifically, use the head-to-head above; over the year, Porto carries the slightly higher overall climate score. Choose San Sebastian if its strong months and profile match your plan, Porto if its do. The month-by-month pages for each destination give you the full picture before you book.