December in Grand Junction averages a daily high of 4.7°C with nights around -6.5°C. Expect roughly 4.2 wet days totalling 12.7mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Grand Junction is April–May.
Based on GRAND JUNCTION 6 ESE, CO US (7.7km), 1995–2024. 29 years of December data.