January in Trier averages a daily high of 4.4°C with nights around -0.4°C. Expect roughly 15.4 wet days totalling 64.5mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Trier is May–September.
Based on TRIER PETRISBERG, GM (1.6km), 1995–2024. 30 years of January data.