The highest day temperature in December 2025 was 56°F. The lowest night temperature was 11°F. The average values for day and night temperatures during December were 35.8°F и 26.2°F respectivly.

The average sea surface temperature in December 2025 for New London was 45.6°F. The maximum and minimum values were 41.0°F and 51.0°F respectively.

Most of the days in December are sunny but you can also expect cloudy and gloomy days.

Precipitation total in December for New London is 1.4 in. This value is relatively stable throughout the year.

The average wind speed in December is 10.2 mph. It makes December the most windy month of the year for New London.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for New London in December is 5.3 hours.