April in Oslo averages a daily high of 11.1°C with nights around 2.1°C. Expect roughly 10 wet days totalling 48.3mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Oslo is June–September.
Based on OSLO BLINDERN, NO (3.6km), 1995–2024. 30 years of April data.