December weather forecastArlington, MA
December
Weather in December
December in Arlington, Massachusetts features a full swing into winter, presenting cold temperatures and a surge in snowfall. Following November, an evident change towards lower temperatures ensures a chilly end to the year. December experiences an increased snowfall of 4.25" (108mm), marking the onset of winter. Moving into January, the chilly weather persists, exhibiting the continuity of the winter season. Despite the cold, the month still enjoys around 9.1 hours of daylight daily, keeping the festive spirit alive.Temperature
As November shifts into December in Arlington, Massachusetts, a slight alteration in temperatures is observed, with average highs reducing from a chilly 49.1°F (9.5°C) to a wintry 39°F (3.9°C). Arlington records a consistent low-temperature of 29.1°F (-1.6°C) during December nights.Humidity
In December, the average relative humidity in Arlington is 76%.Rainfall
The month with the most rainfall is December, when the rain falls for 9.5 days and typically aggregates up to 2.95" (75mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Arlington, during December, snow falls for 5.5 days and regularly aggregates up to 4.25" (108mm) of snow. Throughout the year, there are 29.6 snowfall days, and 17.8" (452mm) of snow is accumulated.Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 6:54 am and sunset at 4:12 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 4:21 pm EST.
Sunshine
In December, the average sunshine is 4.9h.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 unsafe exposure to UV radiation for ordinary individuals.Note: A maximum high daily UV index of 2 during December translates into the following directions:
Children, infants, and individuals with sensitive skin should be constantly protected from extended sun exposure. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration. Take to heart! Snow reflection can almost magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Arlington, MA
- Average high temperature in December: 39°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is January (33.4°F).
- Average low temperature in December: 29.1°F
The month with the highest average low temperature is July (64.4°F).
The coldest month (with the lowest average low temperature) is January (21.7°F).
Average pressure in December
Arlington, MA
- Average pressure in December: 30.03"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
Arlington, MA
- Average wind speed in December: 8.8mph
The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in December
Arlington, MA
- Average humidity in December: 76%
The month with the highest relative humidity is February (78%).
The month with the lowest relative humidity is April (70%).
Average rainfall in December
Arlington, MA
- Average rainfall in December: 2.95"
The wettest month (with the highest rainfall) is December (2.95").
The driest month (with the least rainfall) is September (1.3").
Average rainfall days in December
Arlington, MA
- Average rainfall days in December: 9.5 days
The months with the highest number of rainy days are May and July (15.3 days).
The month with the least rainy days is January (7.8 days).
Average snowfall in December
Arlington, MA
- Average snowfall in December: 4.25"
The month with the highest snowfall is February (4.72").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Arlington, MA
- Average snowfall days in December: 5.5 days
The month with the highest number of snowfall days is January (7.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Arlington, MA
- Average daylight in December: 9h and 6min
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 6min).
- Average sunshine in December: 4h and 54min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
Arlington, MA
- Average sunshine days in December: 16.8 days
The month with the most sunshine days is November (17.6 days).
The month with the least sunshine days is April (13.3 days).
Average UV index in December
Arlington, 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
Arlington, 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 32).
Average visibility in December
Arlington, MA
- Average visibility in December: 6mi
The months with the highest visibility are January, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is February (5mi).





