Last updated: June 24, 2025
In Williams, United States, the average temperature for December hovers around 3°C (38°F), with extremes ranging from a chilly -7°C (20°F) to a mild 17°C (62°F). During this month, expect 121 mm (4.8 in) of precipitation spread over 12 days, contributing to a high average humidity of 87%. Whether you're exploring the outdoors or cozying up inside, be prepared for a mix of cool and wet conditions!
In December in Williams, the average temperature is 3°C (38°F). Maximums can reach 17°C (62°F), while minimums can drop as low as -7°C (20°F). Be prepared for a mix of chilly and mild weather when traveling during this time!
In Williams in December, the precipitation amount reaches 121 mm (4.8 in) over the course of 12 days.
In Williams in December humidity is 87%. With an average temperature of 3°C (38°F), this humidity feels like a chilly blanket wrapped around you, making travel quite uncomfortable as the cold dampness seeps into your clothes and lingers in the air, often leaving you shivering and longing for warmer, drier conditions.
In Williams in December, the maximum UV index is 2, which corresponds to a low exposure category. With this level of UV radiation, the time to burn is approximately 45 minutes. To learn more about the hourly UV index in Williams, you can visit Hourly UV Index in Williams.
UV Risk Categories
Weather in Williams varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Williams, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 4°C (40°F) | 150 mm (5.9 inches) | 84% | moderate |
| February Weather | 4°C (40°F) | 155 mm (6.1 inches) | 85% | moderate |
| March Weather | 6°C (44°F) | 112 mm (4.4 inches) | 86% | high |
| April Weather | 9°C (49°F) | 91 mm (3.6 inches) | 83% | very high |
| May Weather | 13°C (56°F) | 57 mm (2.3 inches) | 83% | very high |
| June Weather | 18°C (64°F) | 21 mm (0.8 inches) | 83% | extreme |
| July Weather | 22°C (71°F) | 3 mm (0.1 inches) | 78% | very high |
| August Weather | 21°C (71°F) | 6 mm (0.3 inches) | 67% | very high |
| September Weather | 17°C (63°F) | 33 mm (1.3 inches) | 66% | very high |
| October Weather | 11°C (53°F) | 42 mm (1.6 inches) | 77% | high |
| November Weather | 7°C (44°F) | 96 mm (3.8 inches) | 87% | moderate |
| December Weather | 3°C (38°F) | 121 mm (4.8 inches) | 87% | low |