April in Hyesan averages a daily high of 13.6°C with nights around -1.3°C. Expect roughly 10 wet days totalling 30.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Hyesan is May.
Based on HYESAN, KN (0.9km), 1995–2024. 22 years of April data.