April in London averages a daily high of 12.5°C with nights around 1.6°C. Expect roughly 11.9 wet days totalling 80mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit London is May–September.
Based on LONDON CS, ON CA (8.7km), 1995–2024. 22 years of April data.