In December, New Haven typically sees daytime highs of 4.6°C and overnight lows around -4.2°C. Compared to the annual average high of 15.4°C, December runs -10.8°C.
December in New Haven averages a daytime high of 4.6°C and an overnight low of -4.2°C.
December runs -10.8°C compared to New Haven's annual average high of 15.4°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 4.6°C and cooler evenings around -4.2°C.