January in Katori-shi averages a daily high of 10°C with nights around 3°C. Expect roughly 7.8 wet days totalling 91.8mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Katori-shi is May–October.
Based on CHOSHI, JA (36.5km), 1995–2024. 24 years of January data.