December in Viersen averages a daily high of 6.6°C with nights around 1.7°C. Expect roughly 16.7 wet days totalling 70.2mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Viersen is May–September.
Based on TONISVORST, GM (5.4km), 1995–2024. 30 years of December data.