December in Hanford averages a daily high of 13.7°C with nights around 2.5°C. Expect roughly 7.3 wet days totalling 39.2mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Hanford is April–May.
Based on HANFORD 1 S, CA US (1.5km), 1995–2024. 29 years of December data.