July in Oshawa averages a daily high of 25.7°C with nights around 16.4°C. Expect roughly 10 wet days totalling 90.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Oshawa is June–September.
Based on OSHAWA WPCP, ON CA (3.9km), 1995–2024. 23 years of July data.