January in Parsippany averages a daily high of 3.7°C with nights around -5.4°C. Expect roughly 9.6 wet days totalling 86.5mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Parsippany is May–June.
Based on BOONTON 1 SE, NJ US (4.5km), 1995–2024. 23 years of January data.