May in Piscataway averages a daily high of 22.3°C with nights around 10.4°C. Expect roughly 13 wet days totalling 108.1mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Piscataway is May–June.
Based on NEW BRUNSWICK 3 SE, NJ US (3.5km), 1995–2024. 30 years of May data.