August in Haeju averages a daily high of 29°C with nights around 21.4°C. Expect roughly 10 wet days totalling 194.5mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Haeju is September–October.
Based on HAEJU, KN (1.5km), 1995–2024. 18 years of August data.