Last updated: August 22, 2025
In December, the average temperature in Sint-Jan, Belgium hovers around 6°C (43°F). Expect a chilly range, with minimum temperatures dipping to -4°C (26°F) and occasionally reaching a warm 15°C (59°F). Be prepared for some wet weather, as 95 mm (3.8 in) of precipitation is likely over 17 days. With an average humidity of 92%, it's a month where you'll want to stay cozy and dry!
In December in Sint-Jan, the average temperature is 6°C (43°F). Maximums can reach 15°C (59°F), while minimums can drop as low as -4°C (26°F). Be prepared for a range of weather conditions during your travels!
In Sint-Jan in December, the precipitation amount is 95 mm (3.8 in) over the course of 17 days.
In Sint-Jan in December humidity is 92%. With an average temperature of 6°C (43°F), this humidity feels like a damp chill that seeps through your clothes, making outdoor activities uncomfortable and requiring extra layers for warmth while navigating the slick streets.
In Sint-Jan in December, the maximum UV index is 1, which corresponds to a low Exposure Category. This means you have a time to burn of 45 minutes. For more details, you can check the Hourly UV Index in Sint-Jan.
UV Risk Categories
Weather in Sint-Jan varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Sint-Jan, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 5°C (41°F) | 65 mm (2.6 inches) | 91% | low |
| February Weather | 6°C (43°F) | 59 mm (2.3 inches) | 89% | low |
| March Weather | 8°C (46°F) | 64 mm (2.5 inches) | 87% | moderate |
| April Weather | 10°C (51°F) | 36 mm (1.4 inches) | 85% | moderate |
| May Weather | 13°C (57°F) | 61 mm (2.4 inches) | 82% | high |
| June Weather | 18°C (64°F) | 60 mm (2.4 inches) | 82% | very high |
| July Weather | 19°C (66°F) | 50 mm (2.0 inches) | 80% | very high |
| August Weather | 19°C (66°F) | 71 mm (2.8 inches) | 76% | high |
| September Weather | 16°C (61°F) | 51 mm (2.0 inches) | 82% | moderate |
| October Weather | 13°C (55°F) | 82 mm (3.2 inches) | 89% | moderate |
| November Weather | 8°C (47°F) | 56 mm (2.2 inches) | 92% | low |
| December Weather | 6°C (43°F) | 95 mm (3.8 inches) | 92% | low |