December weather forecastWellesley Hills, MA
December
Weather in December
December, the first month of the winter in Wellesley Hills, is still a cold month, with an average temperature ranging between min 28.8°F (-1.8°C) and max 39.2°F (4°C).Temperature
In Wellesley Hills, the beginning of December is marked by a lowered average high-temperature, shifting from November's frosty 49.3°F (9.6°C) to a cold 39.2°F (4°C). December nights cool down to an average low-temperature of 28.8°F (-1.8°C).Humidity
In December, the average relative humidity is 76%.Rainfall
In December, the rain falls for 6.1 days. Throughout December, 0.55" (14mm) of precipitation is accumulated. In Wellesley Hills, during the entire year, the rain falls for 85.9 days and collects up to 5.87" (149mm) of precipitation.Snowfall
Months with snowfall are January through May, November and December. 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
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 6:55 am and sunset at 4:13 pm. On the last day of December, sunrise is at 7:14 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 value of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: In December, an average UV index of 2 transforms into the following instructions:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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
Wellesley Hills, 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).





