September in Kokubu-matsuki averages a daily high of 30.4°C. Expect roughly 11.8 wet days totalling 244.8mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Kokubu-matsuki is April–May.
Based on KAGOSHIMA, JA (28.9km), 1995–2024. 21 years of September data.