Last updated: June 18, 2025
In Waterloo, Canada, the average temperature in December hovers around -5°C (23°F), with extremes ranging from a chilly -27°C (-17°F) to a mild 15°C (60°F). Expect about 86 mm (3.4 in) of precipitation spread across 15 days, complemented by a high average humidity of 89%. Stay warm and dry while exploring this winter wonderland!
In December in Waterloo, the average temperature is -5°C (23°F). Maximum can reach 15°C (60°F), and the minimum can be as low as -27°C (-17°F). Travelers should be prepared for a wide range of temperatures and pack accordingly to enjoy their visit.
In Waterloo in December, the precipitation amount is 86 mm (3.4 in) that falls over a span of 15 days.
In Waterloo in December, humidity is 89%. With an average temperature of -5°C (23°F), this humidity feels like a biting chill that seeps into your bones, making outdoor activities uncomfortable and prompting frequent breaks to warm up indoors.
In Waterloo 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 Waterloo, you can visit Hourly UV Index in Waterloo.
UV Risk Categories
Weather in Waterloo varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Waterloo, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -8°C (18°F) | 93 mm (3.7 inches) | 93% | low |
| February Weather | -7°C (20°F) | 89 mm (3.5 inches) | 92% | moderate |
| March Weather | -2°C (28°F) | 90 mm (3.5 inches) | 86% | moderate |
| April Weather | 5°C (42°F) | 120 mm (4.7 inches) | 85% | high |
| May Weather | 13°C (55°F) | 106 mm (4.2 inches) | 80% | very high |
| June Weather | 17°C (64°F) | 126 mm (5.0 inches) | 74% | very high |
| July Weather | 20°C (69°F) | 123 mm (4.8 inches) | 76% | very high |
| August Weather | 19°C (67°F) | 128 mm (5.0 inches) | 75% | very high |
| September Weather | 15°C (60°F) | 84 mm (3.3 inches) | 78% | high |
| October Weather | 9°C (49°F) | 147 mm (5.8 inches) | 86% | moderate |
| November Weather | 1°C (33°F) | 125 mm (4.9 inches) | 88% | moderate |
| December Weather | -5°C (23°F) | 86 mm (3.4 inches) | 89% | low |