May in Saint-Nazaire averages a daily high of 19.8°C with nights around 9.9°C. Expect roughly 12.1 wet days totalling 63mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Saint-Nazaire is May–September.
Based on NANTES BOUGUENAIS, FR (48.1km), 1995–2024. 30 years of May data.