December weather forecastOsterville, MA
December
Weather in December
The first month of the winter, December, is also a frosty month in Osterville, Massachusetts, with an average temperature varying between 36.5°F (2.5°C) and 43.7°F (6.5°C).Temperature
The shift from November to December coincides with a small decrease in the average high-temperature, down to a chilly 43.7°F (6.5°C) from a fresh 51.3°F (10.7°C). The December average low temperature in Osterville, marginally lower than the daytime high, records at a wintry 36.5°F (2.5°C).Humidity
In Osterville, the average relative humidity in December is 75%.Rainfall
In December, the rain falls for 14.2 days. Throughout December, 3.62" (92mm) of precipitation is accumulated. In Osterville, during the entire year, the rain falls for 157.2 days and collects up to 31.77" (807mm) of precipitation.Snowfall
January through April and December are months with snowfall. December is the first month it typically snows. Throughout December, in the average 4.4 snowfall days, it receives 0.87" (22mm) of snow. Throughout the year, there are 24.1 snowfall days, and 6.1" (155mm) of snow is accumulated.Ocean temperature
In Osterville, in December, the average water temperature is 46°F (7.8°C).Note: Entering waters of 46°F (7.8°C) is life-endangering. A mere moment in 55.4°F (13°C) waters feels piercing cold, and below 50°F (10°C) it can lead to immediate cold shock and cessation of breathing control, depending on body resilience.
Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 6:49 am and sunset at 4:12 pm. On the last day of December, sunrise is at 7:08 am and sunset at 4:21 pm EST.
Sunshine
The month with the least sunshine is December, with an average of 4.6h of sunshine.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 low threat to health from unprotected exposure to Sun's UV rays for the average person.Note: During December, 2 as the daily maximum UV index converts into the following advice:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Take precaution! The reflection from snow can almost double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Osterville, MA
- Average high temperature in December: 43.7°F
The warmest month (with the highest average high temperature) is August (72.5°F).
The month with the lowest average high temperature is January (38.3°F).
- Average low temperature in December: 36.5°F
The month with the highest average low temperature is August (68.2°F).
The coldest month (with the lowest average low temperature) is January (30.4°F).
Average pressure in December
Osterville, MA
- Average pressure in December: 30.03"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Osterville, MA
- Average wind speed in December: 16.1mph
The windiest month (with the highest average wind speed) is January (16.5mph).
The calmest month (with the lowest average wind speed) is August (10.6mph).
Average humidity in December
Osterville, MA
- Average humidity in December: 75%
The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is November (74%).
Average rainfall in December
Osterville, MA
- Average rainfall in December: 3.62"
The wettest month (with the highest rainfall) is October (3.7").
The driest month (with the least rainfall) is August (1.73").
Average rainfall days in December
Osterville, MA
- Average rainfall days in December: 14.2 days
The month with the highest number of rainy days is April (15.8 days).
The month with the least rainy days is February (10.3 days).
Average snowfall in December
Osterville, MA
- Average snowfall in December: 0.87"
The month with the highest snowfall is March (1.93").
The months with the least snowfall are May, June, July, August, September, October and November (0").
Average snowfall days in December
Osterville, MA
- Average snowfall days in December: 4.4 days
The month with the highest number of snowfall days is February (7.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in December
Osterville, MA
- Average sea temperature in December: 46.1°F
The best month for swimming (with the highest average sea temperature) is August (67.5°F).
The coldest month (with the lowest average sea temperature) is March (39°F).
Average daylight in December /
Average sunshine in December
Osterville, MA
- Average daylight in December: 9h and 12min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 4h and 36min
The month with the most sunshine is August (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 4h and 36min).
Average sunshine days in December
Osterville, MA
- Average sunshine days in December: 12.6 days
The month with the most sunshine days is August (17.7 days).
The month with the least sunshine days is February (11.4 days).
Average UV index in December
Osterville, MA
- Average UV index in December: 2
The months with the highest UV index are 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
Osterville, MA
- Average cloud cover in December: 50
The months with the most cloud cover are February and December (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in December
Osterville, 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).





