May in Toronto averages a daily high of 19.1°C with nights around 10°C. Expect roughly 11.4 wet days totalling 61.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Toronto is June–September.
Based on TORONTO CITY, ON CA (4.4km), 1995–2024. 21 years of May data.