December in Osijek averages a daily high of 5.1°C with nights around -1°C. Expect roughly 10.3 wet days totalling 56.9mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Osijek is April–October.
Based on OSIJEK, HR (5.1km), 1995–2024. 29 years of December data.