December in Waterbury averages a daily high of 5.8°C with nights around -3.8°C. Expect roughly 11.1 wet days totalling 110.3mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Waterbury is August–October.
Based on MERIDEN MARKHAM MUNICIPAL AIRPORT, CT US (19.4km), 1995–2024. 26 years of December data.