The highest day temperature in May 2025 was 80°F. The lowest night temperature was 49°F. The average values for day and night temperatures during May were 65.4°F и 55.9°F respectivly.

The average sea surface temperature in May 2025 for San Sebastian was 62.7°F. The maximum and minimum values were 59.8°F and 66.2°F respectively.

You can expect various weather conditions during May. Be ready for sunny, cloudy or even gloomy days.

Precipitation total in May for San Sebastian is 2.9 in.

The average wind speed in May is 6.9 mph.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for San Sebastian in May is 7.9 hours.