The highest day temperature in January 2026 was 48°F. The lowest night temperature was 6°F. The average values for day and night temperatures during January were 31.5°F и 27.0°F respectivly.

The average sea surface temperature in January 2026 for Nantucket was 35.2°F. The maximum and minimum values were 31.0°F and 37.6°F respectively.

Most of the days in January are gloomy but you can also expect sunny days.

Precipitation total in January for Nantucket is 1.5 in. It makes january one of the most rainy months of the year.

The average wind speed in January is 19.0 mph. It makes January one of the most windy months of the year for Nantucket.

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 Nantucket in January is 4.5 hours.