Last updated: June 24, 2025
In December, the average temperature in Watertown, United States hovers around -5°C (23°F). Expect chilling lows of -26°C (-15°F) and occasional highs reaching up to 13°C (56°F). During this month, you can anticipate a total precipitation of 33 mm (1.3 in) spread over 5 days, contributing to a rather damp atmosphere with an average humidity of 84%.
In December in Watertown, average temperature is -5°C (23°F). Maximum can reach 13°C (56°F) and minimum can be as low as -26°C (-15°F). It’s advisable to pack warm clothing and be prepared for cold weather conditions if you plan to travel during this time.
In Watertown in December, the precipitation amount is 33 mm (1.3 in) over the course of 5 days.
In Watertown in December, humidity is 84%. With an average temperature of -5°C (23°F), this humidity feels like an icy blanket wrapping around you, making the cold air bite even deeper and turning travel into a brisk, challenging adventure where each breath comes with a frosty reminder of the chill.
In Watertown 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 Watertown, you can visit Hourly UV Index in Watertown.
UV Risk Categories
Weather in Watertown varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Watertown, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -10°C (15°F) | 22 mm (0.9 inches) | 85% | moderate |
| February Weather | -10°C (14°F) | 17 mm (0.7 inches) | 89% | moderate |
| March Weather | -1°C (31°F) | 48 mm (1.9 inches) | 81% | high |
| April Weather | 5°C (41°F) | 65 mm (2.6 inches) | 82% | high |
| May Weather | 13°C (56°F) | 90 mm (3.6 inches) | 76% | very high |
| June Weather | 21°C (70°F) | 84 mm (3.3 inches) | 81% | very high |
| July Weather | 23°C (73°F) | 81 mm (3.2 inches) | 82% | very high |
| August Weather | 21°C (70°F) | 113 mm (4.4 inches) | 83% | very high |
| September Weather | 17°C (62°F) | 84 mm (3.3 inches) | 82% | very high |
| October Weather | 7°C (46°F) | 80 mm (3.1 inches) | 82% | moderate |
| November Weather | 0°C (33°F) | 25 mm (1.0 inches) | 87% | moderate |
| December Weather | -5°C (23°F) | 33 mm (1.3 inches) | 84% | low |