December in Belgrade averages a daily high of 6.5°C with nights around 0.7°C. Expect roughly 11.8 wet days totalling 61.8mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Belgrade is May–June.
Based on BELGRADE OBSERVATORY, RI (0.5km), 1995–2024. 28 years of December data.