January in Bolu averages a daily high of 5.9°C with nights around -2.7°C. Expect roughly 15.3 wet days totalling 61.3mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Bolu is June–October.
Based on BOLU, TU (0.6km), 1995–2024. 23 years of January data.