In May, San Sebastian typically sees daytime highs of 18.4°C and overnight lows around 10.9°C. Compared to the annual average high of 17.1°C, May runs +1.3°C.
May in San Sebastian averages a daytime high of 18.4°C and an overnight low of 10.9°C.
May runs +1.3°C compared to San Sebastian's annual average high of 17.1°C, ranking #6 of 12 months by warmth.
Plan for daytime highs near 18.4°C and cooler evenings around 10.9°C.