December in Niagara Falls averages a daily high of 2.8°C with nights around -3.9°C. Expect roughly 16.1 wet days totalling 72.8mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Niagara Falls is May–September.
Based on NIAGARA FALLS, NY US (7.8km), 1995–2024. 18 years of December data.