April in Markham averages a daily high of 12.3°C with nights around 1.6°C. Expect roughly 12 wet days totalling 81mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Markham is May–September.
Based on TORONTO NORTH YORK, ON CA (18.6km), 1995–2024. 27 years of April data.