January in Onomichi averages a daily high of 9.9°C. Expect roughly 5.1 wet days totalling 31.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Onomichi is April–May.
Based on FUKUYAMA, JA (5.9km), 1995–2024. 29 years of January data.