April in Zemun averages a daily high of 18.8°C with nights around 8.8°C. Expect roughly 11 wet days totalling 52.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Zemun is May–June.
Based on BELGRADE OBSERVATORY, RI (7.3km), 1995–2024. 30 years of April data.