January in Riverside averages a daily high of 21.2°C with nights around 6.2°C. Expect roughly 5.1 wet days totalling 44.1mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Riverside is October–May.
Based on RIVERSIDE FIRE STATION 3, CA US (0.8km), 1995–2024. 15 years of January data.