December in Mostar averages a daily high of 10.5°C with nights around 5.7°C. Expect roughly 12.4 wet days totalling 159.7mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Mostar is April–May.
Based on MOSTAR, BK (1km), 1995–2024. 16 years of December data.