May in Weymouth averages a daily high of 16°C with nights around 9.2°C. Expect roughly 10.5 wet days totalling 47.4mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Weymouth is June–September.
Based on SWANAGE, UK (35.4km), 1995–2024. 29 years of May data.