Last updated: June 24, 2025
In December, the average temperature in Alturas, United States hovers around -1°C (31°F), with a minimum dipping to -16°C (3°F) and a maximum reaching up to 16°C (61°F). Expect about 69 mm (2.7 in) of precipitation over 11 days, contributing to an average humidity of 86%. Whether you're braving the chill or enjoying the crisp air, be prepared for a cool and damp experience!
In December in Alturas, the average temperature is -1°C (31°F), with maximums reaching up to 16°C (61°F) and minimums plummeting as low as -16°C (3°F). Pack accordingly for your travels, as you'll experience a broad range of temperatures during this time.
In Alturas in December, the total precipitation amount is 69 mm (2.7 in) spread across 11 days.
In Alturas in December humidity is 86%. With an average temperature of -1°C (31°F), this humidity feels like an eerie chill enveloping you, making travel uncomfortable as the damp air bites into your skin and the cold seeps through even the warmest of clothes, creating an atmosphere that is heavy and uninviting.
In Alturas 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 Alturas, you can check the information here.
UV Risk Categories
Weather in Alturas varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Alturas, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 0°C (32°F) | 74 mm (2.9 inches) | 86% | moderate |
| February Weather | 0°C (33°F) | 74 mm (2.9 inches) | 87% | moderate |
| March Weather | 3°C (38°F) | 72 mm (2.9 inches) | 86% | high |
| April Weather | 7°C (45°F) | 54 mm (2.1 inches) | 83% | very high |
| May Weather | 13°C (55°F) | 53 mm (2.1 inches) | 72% | extreme |
| June Weather | 18°C (65°F) | 18 mm (0.7 inches) | 67% | extreme |
| July Weather | 23°C (74°F) | 3 mm (0.1 inches) | 56% | extreme |
| August Weather | 22°C (72°F) | 6 mm (0.2 inches) | 42% | extreme |
| September Weather | 17°C (63°F) | 20 mm (0.8 inches) | 46% | very high |
| October Weather | 9°C (49°F) | 35 mm (1.4 inches) | 67% | high |
| November Weather | 4°C (40°F) | 47 mm (1.8 inches) | 86% | moderate |
| December Weather | -1°C (31°F) | 69 mm (2.7 inches) | 86% | moderate |