September in Tournai averages a daily high of 20.6°C with nights around 11.6°C. Expect roughly 11.5 wet days totalling 54.8mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Tournai is May–September.
Based on LILLE LESQUIN, FR (21km), 1995–2024. 30 years of September data.