January in Newmarket averages a daily high of -2.2°C with nights around -11.1°C. Expect roughly 11.8 wet days totalling 50.4mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Newmarket is May–September.
Based on BALDWIN, ON CA (26.9km), 1995–2024. 19 years of January data.