August in Sinwŏn-ŭp 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 Sinwŏn-ŭp is September–October.
Based on HAEJU, KN (23.2km), 1995–2024. 18 years of August data.