May in Surrey averages a daily high of 18.4°C with nights around 8.8°C. Expect roughly 12 wet days totalling 83.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Surrey is July–September.
Based on CLOVERDALE EAST, BC CA (9.2km), 1995–2024. 18 years of May data.