About San Sebastian, San Sebastian's Climate & Weather History

San Sebastian is a city of approximately 11,600 people in San Sebastian, Puerto Rico. Located in the America/Puerto Rico time zone at 18.3°N latitude.

In 2025, San Sebastian recorded an average annual temperature of 77°F. The hottest temperatures reached 93°F in August; the coolest were 62°F in December. Total precipitation for the year was 57 inches, with the wettest month being April.