August in Incheon averages a daily high of 29.2°C with nights around 22.6°C. Expect roughly 10.8 wet days totalling 433.4mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Incheon is May–June.
Based on INCHEON, KS (6.5km), 1995–2024. 22 years of August data.