September in Naha averages a daily high of 30.7°C with nights around 25.5°C. Expect roughly 13.7 wet days totalling 251.5mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Naha is October–May.
Based on NAHA, JA (1.5km), 1995–2024. 22 years of September data.