December weather forecastChestnut Hill, MA
December
Weather in December
The first month of the winter, December, is also a wintry month in Chestnut Hill, Massachusetts, with an average temperature fluctuating between 39.2°F (4°C) and 28.8°F (-1.8°C).Temperature
A shift in the average high-temperature occurs in December, reducing from a chilly 49.3°F (9.6°C) in November to a cold 39.2°F (4°C). During December, an average low-temperature of 28.8°F (-1.8°C) is observed.Humidity
In Chestnut Hill, the average relative humidity in December is 76%.Rainfall
In Chestnut Hill, in December, during 6.1 rainfall days, 0.55" (14mm) of precipitation is typically accumulated. In Chestnut Hill, during the entire year, the rain falls for 85.9 days and collects up to 5.87" (149mm) of precipitation.Snowfall
January through May, November and December are months with snowfall. The month with the most snowfall is December, when snow falls for 2.6 days and typically aggregates up to 0.91" (23mm) 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 December, sunrise is at 6:54 am and sunset at 4:13 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 4:22 pm EST.
Sunshine
In December, the average sunshine is 4.9h.UV index
The months with the lowest UV index in Chestnut Hill 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 minimal health vulnerability from exposure to the Sun's UV radiation for the average person.Note: The average daily UV index of 2 in December transforms into the following instructions:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck. Remember! The Sun's UV radiation can be magnified almost twofold by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Chestnut Hill, MA
- Average high temperature in December: 39.2°F
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in December: 28.8°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (21.7°F).
Average pressure in December
Chestnut Hill, 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
Chestnut Hill, MA
- Average wind speed in December: 8.6mph
The windiest month (with the highest average wind speed) is January (9.1mph).
The calmest month (with the lowest average wind speed) is August (5.8mph).
Average humidity in December
Chestnut Hill, 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
Chestnut Hill, MA
- Average rainfall in December: 0.55"
The wettest month (with the highest rainfall) is November (0.67").
The driest month (with the least rainfall) is September (0.24").
Average rainfall days in December
Chestnut Hill, MA
- Average rainfall days in December: 6.1 days
The month with the highest number of rainy days is July (10.2 days).
The month with the least rainy days is February (4.1 days).
Average snowfall in December
Chestnut Hill, MA
- Average snowfall in December: 0.91"
The month with the highest snowfall is December (0.91").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Chestnut Hill, MA
- Average snowfall days in December: 2.6 days
The month with the highest number of snowfall days is January (4.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Chestnut Hill, 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
Chestnut Hill, MA
- Average sunshine days in December: 22.2 days
The months with the most sunshine days are January and November (22.5 days).
The month with the least sunshine days is June (17.5 days).
Average UV index in December
Chestnut Hill, 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
Chestnut Hill, MA
- Average cloud cover in December: 46
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
Chestnut Hill, 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).





