April in Helsinki averages a daily high of 8.3°C with nights around 1.2°C. Expect roughly 9.6 wet days totalling 34.2mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Helsinki is June–August.
Based on HELSINKI KAISANIEMI AWS, FI (0.9km), 1995–2024. 30 years of April data.