July in Waterloo averages a daily high of 26.4°C with nights around 14.9°C. Expect roughly 10.4 wet days totalling 90.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Waterloo is May–September.
Based on ROSEVILLE, ON CA (13.6km), 1995–2024. 29 years of July data.