January in Karaj averages a daily high of 8.7°C with nights around 0.4°C. Expect roughly 5.7 wet days totalling 27.6mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Karaj is April.
Based on TEHRAN MEHRABAD, IR (33.8km), 1995–2024. 13 years of January data.