December weather forecastWest Groton, MA
December
Weather in December
December, the first month of the winter in West Groton, is still a cold month, with an average temperature fluctuating between 26.2°F (-3.2°C) and 37.4°F (3°C).Temperature
December brings a decrease in the average high-temperature, falling from November's frosty 47.3°F (8.5°C) to a wintry 37.4°F (3°C). Throughout December, the nighttime temperature averages to a freezing cold 26.2°F (-3.2°C).Humidity
In West Groton, the average relative humidity in December is 78%.Rainfall
December is the month with the most rainfall. Rain falls for 9.7 days and accumulates 2.8" (71mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In West Groton, in December, snow falls for 5.3 days, with typically accumulated 4.45" (113mm) of snow. In West Groton, during the entire year, snow falls for 32.6 days and aggregates up to 22.99" (584mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 6min of daylight.On the first day of the month, sunrise is at 6:57 am and sunset at 4:14 pm. On the last day of December, sunrise is at 7:16 am and sunset at 4:23 pm EST.
Sunshine
The average sunshine in December is 4.9h.UV index
The months with the lowest UV index in West Groton, 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 threat to health from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high daily UV index of 2 during December translates into the following directions:
The majority are not significantly affected by prolonged sun exposure. Infants, children, and those with fair skin must always have protection. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. Always opt for UVA and UVB-resistant sunglasses on radiant days. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
West Groton, MA
- Average high temperature in December: 37.4°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (31.3°F).
- Average low temperature in December: 26.2°F
The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is January (19.4°F).
Average pressure in December
West Groton, MA
- Average pressure in December: 30.04"Hg
The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
West Groton, MA
- Average wind speed in December: 8mph
The windiest month (with the highest average wind speed) is January (8.4mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in December
West Groton, MA
- Average humidity in December: 78%
The month with the highest relative humidity is February (81%).
The month with the lowest relative humidity is April (71%).
Average rainfall in December
West Groton, MA
- Average rainfall in December: 2.8"
The wettest month (with the highest rainfall) is December (2.8").
The driest month (with the least rainfall) is September (1.3").
Average rainfall days in December
West Groton, MA
- Average rainfall days in December: 9.7 days
The month with the highest number of rainy days is May (15.5 days).
The month with the least rainy days is February (7.7 days).
Average snowfall in December
West Groton, MA
- Average snowfall in December: 4.45"
The month with the highest snowfall is February (6.3").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
West Groton, MA
- Average snowfall days in December: 5.3 days
The month with the highest number of snowfall days is January (8.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
West Groton, MA
- Average daylight in December: 9h and 6min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 54min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
West Groton, MA
- Average sunshine days in December: 17.7 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is May (13.5 days).
Average UV index in December
West Groton, 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
West Groton, MA
- Average cloud cover in December: 47
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in December
West Groton, MA
- Average visibility in December: 6mi
The months with the highest visibility are April, October, November and December (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August and September (5mi).





