Last updated: August 23, 2025
In San Rafael Arriba, Costa Rica, the average temperature in September hovers around 19°C (66°F), with a comfortable range from a minimum of 14°C (58°F) to a maximum of 25°C (78°F). Expect heavy rainfall during this month, with about 379 mm (14.9 in) of precipitation spread across 29 days. Coupled with an average humidity of 81%, it's wise to prepare for a humid and often wet experience.
In September in San Rafael Arriba, the average temperature is 19°C (66°F). The maximum can reach 25°C (78°F), while the minimum can be as low as 14°C (58°F). This mild weather makes it an ideal time for outdoor exploration and sightseeing.
In San Rafael Arriba in September, the precipitation amount is 379 mm (14.9 in) that falls over a duration of 29 days.
In San Rafael Arriba in September, humidity is 81%. With an average temperature of 19°C (66°F), this humidity feels like a warm, heavy blanket enveloping you, making travel feel both muggy and slightly stifling, often leading to a need for frequent breaks in the shade.
In San Rafael Arriba in September, the maximum UV index is 14, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, so it's crucial to take precautions. For the detailed hourly UV index in San Rafael Arriba, you can check here.
UV Risk Categories
Weather in San Rafael Arriba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in San Rafael Arriba, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 17°C (63°F) | 93 mm (3.7 inches) | 68% | extreme |
| February Weather | 17°C (64°F) | 43 mm (1.7 inches) | 68% | extreme |
| March Weather | 18°C (64°F) | 49 mm (1.9 inches) | 66% | extreme |
| April Weather | 19°C (66°F) | 113 mm (4.4 inches) | 67% | extreme |
| May Weather | 19°C (67°F) | 425 mm (16.7 inches) | 69% | extreme |
| June Weather | 19°C (67°F) | 341 mm (13.4 inches) | 84% | extreme |
| July Weather | 19°C (66°F) | 266 mm (10.5 inches) | 85% | extreme |
| August Weather | 19°C (66°F) | 304 mm (12.0 inches) | 82% | extreme |
| September Weather | 19°C (66°F) | 379 mm (14.9 inches) | 81% | extreme |
| October Weather | 19°C (66°F) | 517 mm (20.4 inches) | 80% | extreme |
| November Weather | 18°C (65°F) | 260 mm (10.3 inches) | 80% | extreme |
| December Weather | 18°C (64°F) | 156 mm (6.1 inches) | 72% | extreme |