April in Waltham averages a daily high of 14.9°C with nights around 2.5°C. Expect roughly 12.5 wet days totalling 98.9mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Waltham is May–June.
Based on BEDFORD HANSCOM FIELD, MA US (11.3km), 1995–2024. 26 years of April data.