March in New Haven averages a daily high of 8.9°C with nights around -0.3°C. Expect roughly 9.9 wet days totalling 89.3mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit New Haven is May–June.
Based on NEW HAVEN TWEED AIRPORT, CT US (6.4km), 1995–2024. 23 years of March data.