May in Plymouth averages a daily high of 20.7°C with nights around 8.7°C. Expect roughly 12.7 wet days totalling 112.2mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Plymouth is May–September.
Based on NEW HOPE, MN US (6km), 1995–2024. 30 years of May data.