September Weather in San Sebastian

Last updated: March 2, 2024

The weather in San Sebastian, Spain, during September is characterized by an average temperature of 18°C (65°F). Highs can soar to 28°C (82°F), while lows may dip to 10°C (51°F). Typically, the humidity level in San Sebastian throughout September hovers around 75%.

10°C (51°F)

Minimum temperature

18°C (65°F)

Average temperature

28°C (82°F)

Maximum temperature

75%

Humidity

Precipitation and Sunshine hours

In September, San Sebastian averages 97 mm (3.8 inches) of rainfall, typically over the course of 12 rainy days. The month enjoys an average of 12 hours 27 minutes of daylight, with the sun shining for approximately 11 hours 10 minutes each day. Additionally, there is a 28% probability of sunny days during this period.

97 mm (3.8 inches)

Precipitation

12 rainy days

Rainy days

11 hours 10 minutes

Sunshine hours

28%

Chance of sun

UV Index

In September, the UV Index in San Sebastian reaches a maximum of 7, indicating a level of High exposure. The most intense UV radiation typically occurs between 13:00 and 15:00, during which unprotected skin may burn in as little as 25 minutes.

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
  07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00
UVI 0 1 1 2 4 5 7 7 7 5 4 2 1
Exposure Low Moderate High Moderate Low
Time to burn 45 min 30 min 25 min 30 min 45 min

Compare San Sebastian's Climate with Cities Worldwide