Last updated: August 27, 2025
In December, the average temperature in San Juan, Peru is a pleasant 19°C (66°F). Expect a minimum of 15°C (59°F) and a maximum of 23°C (75°F), making it a great time to enjoy the outdoors. With an average humidity of 83%, you might feel a bit of moisture in the air, but overall, conditions remain comfortable. Don't worry too much about rain, as the precipitation is only 6 mm (0.2 in) over 0 days!
In December in San Juan, the average temperature is 19°C (66°F). Maximums can reach 23°C (75°F), while minimums can drop to as low as 15°C (59°F). This climate makes San Juan an ideal destination for travelers seeking mild and comfortable weather.
In San Juan in December, the total precipitation amount is 6 mm (0.2 in), spread over a duration of 0 days.
In San Juan in December, humidity is 83%. With an average temperature of 19°C (66°F), this humidity feels like a heavy blanket wrapping around you, making travel feel more sluggish and muggy, yet there's a refreshing coolness in the air that invites you to explore.
In San Juan in December, the maximum UV index reaches an alarming 15, which falls into the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take precautions. For detailed information, you can check the Hourly UV Index in San Juan.
UV Risk Categories
Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 21°C (70°F) | 14 mm (0.6 inches) | 85% | extreme |
| February Weather | 21°C (71°F) | 11 mm (0.4 inches) | 85% | extreme |
| March Weather | 21°C (70°F) | 5 mm (0.2 inches) | 86% | extreme |
| April Weather | 19°C (67°F) | 3 mm (0.1 inches) | 88% | extreme |
| May Weather | 17°C (63°F) | 5 mm (0.2 inches) | 85% | very high |
| June Weather | 16°C (61°F) | 9 mm (0.4 inches) | 78% | very high |
| July Weather | 15°C (59°F) | 11 mm (0.4 inches) | 75% | very high |
| August Weather | 14°C (58°F) | 6 mm (0.2 inches) | 73% | extreme |
| September Weather | 15°C (58°F) | 6 mm (0.2 inches) | 74% | extreme |
| October Weather | 15°C (60°F) | 5 mm (0.2 inches) | 78% | extreme |
| November Weather | 17°C (63°F) | 4 mm (0.2 inches) | 82% | extreme |
| December Weather | 19°C (66°F) | 6 mm (0.2 inches) | 83% | extreme |