December in Arnsberg averages a daily high of 6.5°C with nights around 0.7°C. Expect roughly 18.3 wet days totalling 71.3mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Arnsberg is May–September.
Based on ARNSBERG NEHEIM, GM (11.6km), 1995–2024. 20 years of December data.