Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
The transition into December involves a decrease in the average high-temperature, falling from a frosty 49.1°F (9.5°C) in November to a wintry 39°F (3.9°C). Belmont, during the month of December, experiences an average low-temperature of 29.1°F (-1.6°C).Humidity
In December, the average relative humidity is 76%.Rainfall
December is the month with the most rainfall. Rain falls for 9.5 days and accumulates 2.95" (75mm) of precipitation.Snowfall
Months with snowfall in Belmont are January through May, October through December. In Belmont, during December, snow falls for 5.5 days and regularly aggregates up to 4.25" (108mm) of snow. In Belmont, during the entire year, snow falls for 29.6 days and aggregates up to 17.8" (452mm) of snow.Daylight
With an average of 9h and 6min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 6:54 am and sunset at 4:12 pm. On the last day of December, sunrise is at 7:13 am and sunset at 4:22 pm EST.
Sunshine
In Belmont, Massachusetts, the average sunshine in December is 4.9h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum high UV index of 2 in December translates into the following recommendations:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage. Heed this! Snow reflection can almost augment the UV radiation of the sun by double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
What is the rainiest month?
How many days does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December in Belmont?
When is the sunrise / sunset in December?
How long on average sun shines in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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 6min).
- Average sunshine in December: 4h and 5min
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
Belmont, 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
Belmont, 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
Belmont, 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
Belmont, 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).
Belmont, Massachusetts, USA
Weather forecast for your location
2. Allow the app to use your location