Last updated: August 27, 2025
In San Juan, Philippines, the average temperature in September hovers around 27°C (81°F), with a comfortable minimum of 24°C (75°F) and a peak of 32°C (90°F). Expect 420 mm (16.5 in) of precipitation spread over 28 days, contributing to a notably high average humidity of 82%. Prepare for a warm and wet experience!
In September in San Juan, the average temperature is 27°C (81°F), with maximums reaching up to 32°C (90°F) and minimums dropping as low as 24°C (75°F). This warm weather makes it an ideal time for outdoor activities and exploring what San Juan has to offer.
In San Juan in September, the total precipitation amount is 420 mm (16.5 in) spread over 28 days.
In San Juan in September humidity is 82%. With an average temperature of 27°C (81°F), this humidity feels like a heavy blanket wrapping around you, making outdoor activities feel more exhausting, and leaving you longing for the relief of air-conditioned spaces during your travels.
In San Juan 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 Juan, you can check here.
UV Risk Categories
Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 26°C (79°F) | 36 mm (1.4 inches) | 74% | extreme |
| February Weather | 26°C (79°F) | 27 mm (1.1 inches) | 73% | extreme |
| March Weather | 27°C (81°F) | 37 mm (1.4 inches) | 74% | extreme |
| April Weather | 28°C (82°F) | 52 mm (2.1 inches) | 76% | extreme |
| May Weather | 28°C (83°F) | 140 mm (5.5 inches) | 76% | extreme |
| June Weather | 27°C (82°F) | 419 mm (16.5 inches) | 79% | extreme |
| July Weather | 27°C (80°F) | 659 mm (25.9 inches) | 83% | extreme |
| August Weather | 26°C (80°F) | 680 mm (26.8 inches) | 83% | extreme |
| September Weather | 27°C (81°F) | 420 mm (16.5 inches) | 82% | extreme |
| October Weather | 27°C (81°F) | 243 mm (9.6 inches) | 80% | extreme |
| November Weather | 27°C (81°F) | 130 mm (5.1 inches) | 84% | very high |
| December Weather | 27°C (80°F) | 65 mm (2.6 inches) | 81% | very high |