About Raritan, NJ's Climate & Weather History

With a population of around 8,000, Raritan sits in New Jersey, United States. The city operates in the Eastern Time Zone.

In 2025, Raritan recorded an average annual temperature of 54°F — about 1.8°F above the 30-year normal of 53°F. The hottest day reached 101°F in June; the coldest was 4°F in January. Total precipitation was 39 inches (drier than usual). The wettest month was May.