Last updated: June 24, 2025
In December, the average temperature in Williamstown, United States hovers around -5°C (24°F), with extremes that can plummet to -28°C (-18°F) and reach a maximum of 14°C (57°F). Expect 88 mm (3.4 in) of precipitation spread across 13 days, contributing to an average humidity of 84%. Stay prepared for a chilly and damp environment!
In December in Williamstown, the average temperature is -5°C (24°F). Maximums can reach 14°C (57°F), while minimums can drop as low as -28°C (-18°F). Travelers should be prepared for a wide range of temperatures, ensuring they pack layers for both warmer days and frigid nights.
In Williamstown in December, the precipitation amount is 88 mm (3.4 in) occurring over 13 days.
In Williamstown in December, humidity is 84%. With an average temperature of -5°C (24°F), this humidity feels like an icy blanket wrapped around you, making the air feel even colder and more biting, which can be quite uncomfortable for traveling.
In Williamstown 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 Williamstown, you can visit Hourly UV Index in Williamstown.
UV Risk Categories
Weather in Williamstown varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Williamstown, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -7°C (19°F) | 77 mm (3.0 inches) | 89% | low |
| February Weather | -6°C (22°F) | 80 mm (3.2 inches) | 88% | moderate |
| March Weather | -2°C (29°F) | 71 mm (2.8 inches) | 86% | moderate |
| April Weather | 5°C (42°F) | 117 mm (4.6 inches) | 84% | very high |
| May Weather | 12°C (55°F) | 96 mm (3.8 inches) | 76% | very high |
| June Weather | 17°C (64°F) | 97 mm (3.8 inches) | 72% | very high |
| July Weather | 20°C (69°F) | 140 mm (5.5 inches) | 66% | very high |
| August Weather | 19°C (67°F) | 98 mm (3.9 inches) | 64% | very high |
| September Weather | 15°C (60°F) | 71 mm (2.8 inches) | 72% | high |
| October Weather | 9°C (48°F) | 141 mm (5.6 inches) | 81% | moderate |
| November Weather | 1°C (33°F) | 104 mm (4.1 inches) | 87% | moderate |
| December Weather | -5°C (24°F) | 88 mm (3.4 inches) | 84% | low |