Waltham Weather Outlook: August 13–20, 2026

Waltham will transition into a much more comfortable weather pattern as we head toward the weekend. A cold front moving through today will bring an end to the recent stretch of higher humidity, with cooler and noticeably drier air arriving tonight. Friday and Saturday look particularly pleasant with sunshine, seasonable temperatures, and low humidity. Moisture returns later Sunday, with the next opportunity for widespread rain arriving Sunday night into Monday. Drier weather should follow for much of the middle of next week.