April in Kotka averages a daily high of 6.2°C with nights around 0.3°C. Expect roughly 8.7 wet days totalling 27.2mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Kotka is June–August.
Based on KOTKA RANKKI, FI (10.2km), 1995–2024. 30 years of April data.