May in Hoorn averages a daily high of 17.4°C with nights around 7.8°C. Expect roughly 11.9 wet days totalling 54.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Hoorn is June–September.
Based on BERKHOUT, NL (5.5km), 1995–2024. 26 years of May data.