Last updated: June 24, 2025
In December, the average temperature in San Martin, United States hovers around 10°C (50°F), with a potential drop to a chilly -2°C (30°F) or a warm peak of 23°C (74°F). Expect about 79 mm (3.1 in) of precipitation spread over 8 days, contributing to an average humidity level of 80%. Whether you're braving the cool breezes or enjoying the sun, plan your activities accordingly!
In December in San Martin, the average temperature is 10°C (50°F). Maximum can reach 23°C (74°F) and minimum can be as low as -2°C (30°F). This variation in temperature makes it essential for travelers to pack layers to accommodate both warm and chilly conditions.
In San Martin in December, the precipitation amount is 79 mm (3.1 in) during 8 days, indicating a relatively wet period for the area.
In San Martin in December, humidity is 80%. With an average temperature of 10°C (50°F), this humidity feels like a damp chill enveloping you, making traveling somewhat uncomfortable as it seeps into your clothes and clings to your skin, leaving you longing for a cozy indoor refuge.
In San Martin in December, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in San Martin, you can check the information here.
UV Risk Categories
Weather in San Martin varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Martin, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 10°C (50°F) | 103 mm (4.0 inches) | 82% | moderate |
| February Weather | 11°C (52°F) | 79 mm (3.1 inches) | 84% | moderate |
| March Weather | 12°C (53°F) | 73 mm (2.9 inches) | 82% | very high |
| April Weather | 14°C (57°F) | 26 mm (1.0 inches) | 78% | very high |
| May Weather | 15°C (60°F) | 15 mm (0.6 inches) | 71% | extreme |
| June Weather | 18°C (65°F) | 1 mm (0.0 inches) | 64% | extreme |
| July Weather | 19°C (67°F) | 1 mm (0.0 inches) | 58% | extreme |
| August Weather | 20°C (68°F) | 1 mm (0.0 inches) | 54% | very high |
| September Weather | 19°C (67°F) | 2 mm (0.1 inches) | 55% | very high |
| October Weather | 17°C (62°F) | 17 mm (0.7 inches) | 62% | high |
| November Weather | 13°C (55°F) | 30 mm (1.2 inches) | 78% | moderate |
| December Weather | 10°C (50°F) | 79 mm (3.1 inches) | 80% | moderate |