Last updated: August 27, 2025
In San Juan, Peru, the average temperature in December hovers around 26°C (79°F), making for a warm and inviting atmosphere. Daily temperatures can vary significantly, with a minimum of 22°C (72°F) and a maximum reaching up to 34°C (94°F). However, visitors should be prepared for the wet conditions, as the region experiences 273 mm (10.7 in) of precipitation spread over 27 days, contributing to a high average humidity of 88%.
In December in San Juan, the average temperature is 26°C (79°F), with maximums reaching 34°C (94°F) and minimums dropping as low as 22°C (72°F). This mild and warm climate makes San Juan an ideal destination for travelers seeking pleasant weather.
In San Juan in December, the total precipitation amount is 273 mm (10.7 in) spread over 27 days.
In San Juan in December, humidity is 88%. With an average temperature of 26°C (79°F), this humidity feels like a warm blanket wrapped around you, making travel somewhat uncomfortable as you quickly become aware of the stickiness and heaviness in the air.
In San Juan in December, the maximum UV index reaches 13, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take protective measures. 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 | 26°C (79°F) | 251 mm (9.9 inches) | 84% | extreme |
| February Weather | 26°C (79°F) | 226 mm (8.9 inches) | 82% | extreme |
| March Weather | 26°C (79°F) | 321 mm (12.7 inches) | 84% | extreme |
| April Weather | 26°C (79°F) | 305 mm (12.0 inches) | 87% | extreme |
| May Weather | 26°C (79°F) | 223 mm (8.8 inches) | 89% | extreme |
| June Weather | 25°C (78°F) | 193 mm (7.6 inches) | 82% | extreme |
| July Weather | 25°C (78°F) | 145 mm (5.7 inches) | 69% | extreme |
| August Weather | 26°C (79°F) | 107 mm (4.2 inches) | 58% | extreme |
| September Weather | 26°C (80°F) | 152 mm (6.0 inches) | 56% | extreme |
| October Weather | 26°C (80°F) | 188 mm (7.4 inches) | 62% | extreme |
| November Weather | 26°C (80°F) | 233 mm (9.2 inches) | 77% | extreme |
| December Weather | 26°C (79°F) | 273 mm (10.7 inches) | 88% | extreme |