October in Belleville averages a daily high of 14.8°C with nights around 6.2°C. Expect roughly 12.9 wet days totalling 87.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Belleville is May–September.
Based on BELLEVILLE, ON CA (2.3km), 1995–2024. 25 years of October data.