About San Sebastian, Retalhuleu's Climate & Weather History

With a population of around 29,200, San Sebastian sits in Retalhuleu, Guatemala. The city operates in the America/Guatemala time zone.

In 2025, San Sebastian recorded an average annual temperature of 77°F. The hottest temperatures reached 95°F in April; the coolest were 62°F in April. Total precipitation for the year was 73 inches, with the wettest month being October.