January in Downtown DC averages a daily high of 6.9°C with nights around -2.8°C. Expect roughly 9.3 wet days totalling 79.6mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Downtown DC is April–May.
Based on NATIONAL ARBORETUM DC, MD US (4.8km), 1995–2024. 26 years of January data.