Chelsea
Massachusetts, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Chelsea, MA

Ocean temperature

In Chelsea, Massachusetts, the average seawater temperature in December is 46.8°F (8.2°C).
Note: Swimming in 46.8°F (8.2°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

Daylight

With an average of 9.1h of daylight, December has the shortest days of the year in Chelsea.

What is the water temperature in December in Chelsea?

In Chelsea, the average seawater temperature in December is 46.8°F (8.2°C). Swimming in 46.8°F (8.2°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

What is the month with the shortest days in Chelsea?

With an average of 9.1h of daylight, December has the shortest days of the year.

What is the average length of the day in December in Chelsea?

The average length of the day in December in Chelsea is 9.1h.
Average sea temperature in December - Chelsea, MA
  • Average sea temperature in December: 46.6°F

The best month for swimming (with the highest average sea temperature) is August (67.9°F).
The coldest month (with the lowest average sea temperature) is February (38.1°F).

Average daylight in December - Chelsea, MA
  • Average daylight in December: 9.1h

The month with the longest days is June (Average daylight: 15.2h).
The month with shortest days is December (Average daylight: 9.1h).