September in Yamatokōriyama averages a daily high of 28.7°C. Expect roughly 11.4 wet days totalling 161.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Yamatokōriyama is April–June.
Based on NARA, JA (11.9km), 1995–2024. 26 years of September data.