Climate almanac
San Juan
San José, Costa Rica · 9.96°, -84.08°
What is the weather like in San Juan in September?
In September, San Juan is typically 74°F (23°C) during the day and 61°F (16°C) at night. The month brings about 14 in (362 mm) of precipitation in total.
- Average high74°F (23°C)
- Average low61°F (16°C)
- Precipitation14 in (362 mm)
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)