Last updated: August 27, 2025
In December, the average temperature in San Luis, Peru is a crisp 9°C (49°F). Expect chilly nights, with minimums dipping to 1°C (33°F), while daytime highs can reach up to 19°C (67°F). The month brings substantial rainfall, with approximately 250 mm (9.9 in) spread over 29 days, contributing to an average humidity of a humid 91%. Be prepared for wet and cool conditions!
In December in San Luis, the average temperature is 9°C (49°F). The maximum can reach 19°C (67°F), while the minimum can dip as low as 1°C (33°F). It's advisable to pack layers to stay comfortable during your travels.
In San Luis in December, the total precipitation amount is 250 mm (9.9 in) over the course of 29 days.
In San Luis in December humidity is 91%. With an average temperature of 9°C (49°F), this humidity feels like a chilly mist enveloping you, making travel uncomfortable as the dampness seeps into your clothing and chills you to the bone.
In San Luis in December, the maximum UV index reaches an alarming 17, which falls under the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to stay protected. For more details on the hourly UV index in San Luis, you can check Hourly UV Index in San Luis.
UV Risk Categories
Weather in San Luis varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Luis, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 9°C (48°F) | 240 mm (9.4 inches) | 88% | extreme |
| February Weather | 9°C (49°F) | 223 mm (8.8 inches) | 86% | extreme |
| March Weather | 9°C (48°F) | 271 mm (10.7 inches) | 89% | extreme |
| April Weather | 9°C (48°F) | 160 mm (6.3 inches) | 89% | extreme |
| May Weather | 9°C (48°F) | 87 mm (3.4 inches) | 86% | extreme |
| June Weather | 8°C (47°F) | 45 mm (1.8 inches) | 71% | extreme |
| July Weather | 8°C (46°F) | 36 mm (1.4 inches) | 44% | extreme |
| August Weather | 8°C (47°F) | 43 mm (1.7 inches) | 34% | extreme |
| September Weather | 8°C (47°F) | 97 mm (3.8 inches) | 37% | extreme |
| October Weather | 9°C (48°F) | 179 mm (7.1 inches) | 50% | extreme |
| November Weather | 9°C (49°F) | 222 mm (8.7 inches) | 73% | extreme |
| December Weather | 9°C (49°F) | 250 mm (9.9 inches) | 91% | extreme |