Last updated: June 24, 2025
In December, the average temperature in Willoughby, United States hovers around 3°C (37°F). Expect a chill that can dip to a minimum of -9°C (15°F) and may peak at a comfortable 13°C (56°F). With about 115 mm (4.5 in) of precipitation spread over 17 days, you’ll want to be prepared for wet weather. The air stays quite damp, with an average humidity of 86%, so dress warmly and enjoy the cool, misty ambiance!
In December in Willoughby, the average temperature is 3°C (37°F). The maximum can reach 13°C (56°F) and the minimum can be as low as -9°C (15°F). Travelers should be prepared for chilly weather and dress in layers to stay comfortable during their visit.
In Willoughby, in December, the precipitation amount is 115 mm (4.5 in) over the course of 17 days.
In Willoughby in December humidity is 86%. With an average temperature of 3°C (37°F), this humidity feels like a damp chill that seeps into your bones, making outdoor activities uncomfortable and travel less enjoyable.
In Willoughby 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 Willoughby, you can visit Hourly UV Index in Willoughby.
UV Risk Categories
Weather in Willoughby varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Willoughby, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -1°C (31°F) | 100 mm (3.9 inches) | 88% | moderate |
| February Weather | -1°C (31°F) | 100 mm (3.9 inches) | 88% | moderate |
| March Weather | 2°C (35°F) | 97 mm (3.8 inches) | 87% | high |
| April Weather | 6°C (43°F) | 114 mm (4.5 inches) | 87% | very high |
| May Weather | 12°C (54°F) | 112 mm (4.4 inches) | 81% | very high |
| June Weather | 19°C (66°F) | 92 mm (3.6 inches) | 83% | very high |
| July Weather | 23°C (73°F) | 104 mm (4.1 inches) | 82% | very high |
| August Weather | 23°C (73°F) | 77 mm (3.0 inches) | 76% | very high |
| September Weather | 20°C (68°F) | 91 mm (3.6 inches) | 77% | very high |
| October Weather | 15°C (59°F) | 139 mm (5.5 inches) | 82% | high |
| November Weather | 7°C (44°F) | 137 mm (5.4 inches) | 89% | moderate |
| December Weather | 3°C (37°F) | 115 mm (4.5 inches) | 86% | low |