January in Gaithersburg averages a daily high of 4.2°C with nights around -3.8°C. Expect roughly 10.2 wet days totalling 87.4mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Gaithersburg is August–October.
Based on DAMASCUS 3 SSW, MD US (13.8km), 1995–2024. 30 years of January data.