December weather forecast
West Dennis, MA

Share

Weather in December

December, the first month of the winter in West Dennis, is also a frosty month, with an average temperature varying between 43.7°F (6.5°C) and 36.9°F (2.7°C).

Temperature

As December begins, there is a minor decrease in the average high-temperature, softly falling from a fresh 51.3°F (10.7°C) in November to a chilly 43.7°F (6.5°C). West Dennis sees a minor drop to an average minimum temperature of 36.9°F (2.7°C) during the night in the month of December.

Humidity

In December, the average relative humidity is 75%.

Rainfall

In West Dennis, during December, the rain falls for 10.8 days and regularly aggregates up to 1.38" (35mm) of precipitation. Throughout the year, there are 129 rainfall days, and 14.21" (361mm) of precipitation is accumulated.

Snowfall

January through April and December are months with snowfall in West Dennis. December is the first month it typically snows. Throughout December, in the average 4.5 snowfall days, it receives 0.39" (10mm) of snow. In West Dennis, during the entire year, snow falls for 20.8 days and aggregates up to 2.6" (66mm) of snow.

Ocean temperature

In December, the average ocean temperature is 46°F (7.8°C).
Note: With an efficient thermal swimsuit, one can navigate 46°F (7.8°C) even if it's colder than 50°F (10°C); otherwise, rapid cold shock and breathlessness might set in. Barely wading at 55.4°F (13°C) feels chilly.

Daylight

December has the shortest days of the year, with an average of 9h and 12min of daylight.
On the first day of December, sunrise is at 6:48 am and sunset at 4:11 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 4:20 pm EST.

Sunshine

The months with the least sunshine are February and December, with an average of 4.6h of sunshine.

UV index

January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: The daily high UV index of 2 during December translates into the following recommendations:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Updated: Aug 17, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How cold does it get in December?

In West Dennis, 43.7°F (6.5°C) is the average high-temperature and 36.9°F (2.7°C) is the average low-temperature during December.

What is the average humidity in December?

The average relative humidity in December is 75%.

How many days does it rain in December?

In West Dennis, in December, it is raining for 10.8 days, with typically 1.38" (35mm) of accumulated precipitation.

When does it start snowing?

December is the first month it typically snows. Throughout December, in the average 4.5 snowfall days, it receives 0.39" (10mm) of snow.

What is the water temperature in December?

In West Dennis, the average seawater temperature in December is 46°F (7.8°C). At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

What is the month with the shortest days?

December has the shortest days of the year in West Dennis, with an average of 9h and 12min of daylight.

How many hours of daylight does West Dennis have in December?

In December, the average day length is 9h and 13min.

When is the sunrise / sunset in December?

In December, on the first day of the month, sunrise is at 6:48 am and sunset at 4:11 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 4:20 pm EST.

What are the months with the least sunshine?

The months with the least sunshine are February and December, with an average of 4.6h of sunshine.

How many hours of sunshine does West Dennis have in December?

The average sunshine duration in December in West Dennis is 4.6h.

What is the month with the lowest UV index?

January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index.

What is the UV index intensity in December?

The average daily maximum UV index in December is 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
West Dennis, MA

Average temperature in December - West Dennis, MA
  • Average high temperature in December: 43.7°F

The warmest month (with the highest average high temperature) is August (72.1°F).
The month with the lowest average high temperature is January (38.5°F).

  • Average low temperature in December: 36.9°F

The month with the highest average low temperature is August (68.5°F).
The coldest month (with the lowest average low temperature) is January (30.6°F).

Average pressure in December
West Dennis, MA

Average pressure in December - West Dennis, MA
  • Average pressure in December: 30.03"Hg

The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).

Average wind speed in December
West Dennis, MA

Average wind speed in December - West Dennis, MA
  • Average wind speed in December: 16.4mph

The windiest month (with the highest average wind speed) is January (16.8mph).
The calmest months (with the lowest average wind speed) are July and August (10.9mph).

Average humidity in December
West Dennis, MA

Average humidity in December - West Dennis, MA
  • Average humidity in December: 75%

The months with the highest relative humidity are June and July (84%).
The month with the lowest relative humidity is November (74%).

Average rainfall in December
West Dennis, MA

Average rainfall in December - West Dennis, MA
  • Average rainfall in December: 1.38"

The wettest month (with the highest rainfall) is October (1.93").
The driest month (with the least rainfall) is August (0.94").

Average rainfall days in December
West Dennis, MA

Average rainfall days in December - West Dennis, MA
  • Average rainfall days in December: 10.8 days

The month with the highest number of rainy days is May (12.5 days).
The month with the least rainy days is February (8.3 days).

Average snowfall in December
West Dennis, MA

Average snowfall in December - West Dennis, MA
  • Average snowfall in December: 0.39"

The month with the highest snowfall is January (0.87").
The months with the least snowfall are May, June, July, August, September, October and November (0").

Average snowfall days in December
West Dennis, MA

Average snowfall days in December - West Dennis, MA
  • Average snowfall days in December: 4.5 days

The month with the highest number of snowfall days is January (6.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average sea temperature in December
West Dennis, MA

Average sea temperature in December - West Dennis, MA
  • Average sea temperature in December: 46.1°F

The best month for swimming (with the highest average sea temperature) is August (67.5°F).
The coldest month (with the lowest average sea temperature) is March (39°F).

Average daylight in December /
Average sunshine in December
West Dennis, MA

Average daylight in December / Average sunshine in December - West Dennis, MA
  • Average daylight in December: 9h and 1min

The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).

  • Average sunshine in December: 4h and 4min

The month with the most sunshine is August (Average sunshine: 10h and 48min).
The months with the least sunshine are February and December (Average sunshine: 4h and 36min).

Average sunshine days in December
West Dennis, MA

Average sunshine days in December - West Dennis, MA
  • Average sunshine days in December: 15.3 days

The month with the most sunshine days is September (18.6 days).
The month with the least sunshine days is February (14.3 days).

Average UV index in December
West Dennis, MA

Average UV index in December - West Dennis, MA
  • Average UV index in December: 2

The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).

Average cloud cover in December
West Dennis, MA

Average cloud cover in December - West Dennis, MA
  • Average cloud cover in December: 51

The month with the most cloud cover is December (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 27).

Average visibility in December
West Dennis, MA

Average visibility in December - West Dennis, MA
  • Average visibility in December: 6mi

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

West Dennis, Massachusetts, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location