January in Waltham averages a daily high of 2.3°C with nights around -7.7°C. Expect roughly 10.7 wet days totalling 70.3mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Waltham is May–June.
Based on BEDFORD HANSCOM FIELD, MA US (11.3km), 1995–2024. 25 years of January data.