December weather forecastDedham, MA
December
Weather in December
December, the first month of the winter in Dedham, is also a wintry month, with an average temperature varying between 29.1°F (-1.6°C) and 39.6°F (4.2°C).Temperature
December shows a mild decline in the average high-temperature, falling from November's chilly 49.3°F (9.6°C) to an icy 39.6°F (4.2°C). The average nighttime temperature in Dedham lowers to a freezing cold 29.1°F (-1.6°C) throughout December.Humidity
In Dedham, the average relative humidity in December is 77%.Rainfall
The month with the most rainfall is December, when the rain falls for 10.7 days and typically aggregates up to 2.95" (75mm) of precipitation.Snowfall
Months with snowfall in Dedham are January through April, October through December. In Dedham, in December, during 5.8 snowfall days, 4.21" (107mm) of snow is typically accumulated. In Dedham, during the entire year, snow falls for 32.7 days and aggregates up to 22.01" (559mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 12min 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 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 unprotected exposure to Sun's UV rays for the ordinary person.Note: In December, the maximum UV index of 2 transforms into these recommendations:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Dedham, MA
- Average high temperature in December: 39.6°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (33.6°F).
- Average low temperature in December: 29.1°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (21.9°F).
Average pressure in December
Dedham, 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 (29.93"Hg).
Average wind speed in December
Dedham, MA
- Average wind speed in December: 8.9mph
The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is August (6mph).
Average humidity in December
Dedham, MA
- Average humidity in December: 77%
The month with the highest relative humidity is February (78%).
The month with the lowest relative humidity is April (70%).
Average rainfall in December
Dedham, 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 (1.5").
Average rainfall days in December
Dedham, MA
- Average rainfall days in December: 10.7 days
The month with the highest number of rainy days is July (15.8 days).
The months with the least rainy days are January and February (7.8 days).
Average snowfall in December
Dedham, MA
- Average snowfall in December: 4.21"
The month with the highest snowfall is March (5.24").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Dedham, MA
- Average snowfall days in December: 5.8 days
The month with the highest number of snowfall days is February (8.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Dedham, 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 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
Dedham, MA
- Average sunshine days in December: 16.5 days
The month with the most sunshine days is November (18 days).
The month with the least sunshine days is April (13.2 days).
Average UV index in December
Dedham, 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
Dedham, 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 33).
Average visibility in December
Dedham, 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).





