September in Montreuil averages a daily high of 22.5°C with nights around 13.3°C. Expect roughly 9.9 wet days totalling 39.1mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Montreuil is May–September.
Based on PARIS MONTSOURIS, FR (9km), 1995–2024. 21 years of September data.