Brussels · December
Run in the midday.
Cold: average high 46°F, low 38°F. Layering becomes the workout. Humidity averages 88% — the limiting factor on most runs. Expect 18 rain days — plan around the radar. Cold mornings warm into runnable midday hours — the windows around noon catch the warmest temperatures.
Avg high / low
46° / 38°F
Humidity
88%
Rain days
18/mo
Wind
15 mph
What December feels like in Brussels
Sunrise
09:37
Mid-month average
Sunset
17:39
Mid-month average
Time-of-day breakdown
Morning
Coolest, driest air of the day. The window before sunrise is the most reliable comfortable hour.
Midday
Mild but UV and traffic peak. Workable if you don't mind shifting your pace.
Evening
Warm and runnable. Crowded routes but the air's typically calm.
What to wear running in Brussels in December
The kit for December in Brussels: a long-sleeve or light jacket for the first mile, a wind-blocking layer for exposed routes, a water-resistant cap or jacket on standby.
December vs the surrounding months
vs November
-5° avg high
+1 rain days
Brussels in November →
December
46°F avg high
18 rain days
Best: midday
vs January
+2° avg high
0 rain days
Brussels in January →
Frequently Asked Questions
What is the best time of day to run in Brussels in December?+
Midday. Cold mornings warm into runnable midday hours — the windows around noon catch the warmest temperatures.
What's the average temperature in Brussels in December?+
Average high 46°F, average low 38°F.
How does December compare to surrounding months in Brussels?+
Compared to November (avg high 51°F), December is cooler. Compared to January (avg high 44°F), December is warmer.
Does it rain often in Brussels in December?+
Expect about 18 measurable rain days in December, on average.