September in Kaiyuan averages a daily high of 27.2°C with nights around 18.6°C. Expect roughly 11.7 wet days totalling 79mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Kaiyuan is November–March.
Based on MENGZI, CH (35.9km), 1995–2024. 23 years of September data.