April in Irkutsk averages a daily high of 10.5°C with nights around -1.9°C. Expect roughly 7.2 wet days totalling 23.5mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Irkutsk is May–August.
Based on IRKUTSK, RS (5.2km), 1995–2024. 28 years of April data.