April in Nagaoka averages a daily high of 16.2°C. Expect roughly 13.7 wet days totalling 103.4mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Nagaoka is May–June.
Based on NIIGATA, JA (54.8km), 1995–2024. 22 years of April data.