December weather forecastPlymouth, MA
December
Weather in December
December in Plymouth, Massachusetts, immerses the city in the throes of a classic New England winter. As the city wraps up the year, it welcomes back the cold weather, snowy landscapes, and holiday festivities. A steep increase in snowfall from 0.24" (6mm) in November to 1.02" (26mm) in December reignites the city’s winter charm. Plymouth counters the harsh winter with warmth radiating from brightly lit homes, crackling fireplaces, and holiday cheers. Wrapping up the annual climate cycle, December manages to end on a high note, setting the stage for another year of varied weather delights.Temperature
In December, the average high-temperature marginally drops from a cool 50.7°F (10.4°C) in November to an icy 41.9°F (5.5°C). Plymouth's nighttime average temperature in December drops marginally from the daytime highs, settling at a still wintry 32.9°F (0.5°C).Humidity
The average relative humidity in December in Plymouth, Massachusetts, is 76%.Rainfall
In Plymouth, in December, it is raining for 9.8 days, with typically 1.54" (39mm) of accumulated precipitation. In Plymouth, during the entire year, the rain falls for 132.2 days and collects up to 16.3" (414mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Plymouth, in December, during 4 snowfall days, 1.02" (26mm) of snow is typically accumulated. In Plymouth, during the entire year, snow falls for 23.3 days and aggregates up to 5.87" (149mm) of snow.Ocean temperature
In Plymouth, in December, the average water temperature is 46.9°F (8.3°C).Note: Dipping into 46.9°F (8.3°C) below 50°F (10°C) is possible with the right protection; absent that, anticipate cold shock and hampered breathing. Swimming momentarily at 55.4°F (13°C) can be jarring.
Daylight
With an average of 9h and 12min of daylight, December has the shortest days of the year in Plymouth.On the first day of the month, sunrise is at 6:51 am and sunset at 4:12 pm. On the last day of December, sunrise is at 7:10 am and sunset at 4:21 pm EST.
Sunshine
The months with the least sunshine are February and December, with an average of 4.7h of sunshine.UV index
The months with the lowest UV index in Plymouth, Massachusetts, are January through March, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index of 2 in December interprets into the following recommendations:
Babies, children, and those with sensitive skin should always avoid extended periods in the sun. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation. Be alert to the fact! The reflection from snow can nearly double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Plymouth, MA
- Average high temperature in December: 41.9°F
The warmest month (with the highest average high temperature) is July (77.5°F).
The month with the lowest average high temperature is January (35.8°F).
- Average low temperature in December: 32.9°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in December
Plymouth, 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
Plymouth, MA
- Average wind speed in December: 11.6mph
The windiest month (with the highest average wind speed) is January (12.3mph).
The calmest month (with the lowest average wind speed) is August (7.8mph).
Average humidity in December
Plymouth, MA
- Average humidity in December: 76%
The month with the highest relative humidity is July (80%).
The months with the lowest relative humidity are March, April and November (74%).
Average rainfall in December
Plymouth, MA
- Average rainfall in December: 1.54"
The wettest months (with the highest rainfall) are July and October (1.65").
The driest month (with the least rainfall) is February (1.02").
Average rainfall days in December
Plymouth, MA
- Average rainfall days in December: 9.8 days
The month with the highest number of rainy days is July (14 days).
The month with the least rainy days is January (7.4 days).
Average snowfall in December
Plymouth, MA
- Average snowfall in December: 1.02"
The month with the highest snowfall is March (1.77").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Plymouth, MA
- Average snowfall days in December: 4 days
The month with the highest number of snowfall days is January (7.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in December
Plymouth, MA
- Average sea temperature in December: 46.9°F
The best month for swimming (with the highest average sea temperature) is August (68.4°F).
The coldest month (with the lowest average sea temperature) is February (38.2°F).
Average daylight in December /
Average sunshine in December
Plymouth, MA
- Average daylight in December: 9h and 12min
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 42min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are February and December (Average sunshine: 4h and 42min).
Average sunshine days in December
Plymouth, MA
- Average sunshine days in December: 18.5 days
The month with the most sunshine days is December (18.5 days).
The month with the least sunshine days is July (14.8 days).
Average UV index in December
Plymouth, MA
- Average UV index in December: 2
The months with the highest UV index are June, 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
Plymouth, MA
- Average cloud cover in December: 48
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in December
Plymouth, 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).
