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 arrival of December signals a shift in temperature, down from a frosty 45.1°F (7.3°C) in November to a wintry 34.2°F (1.2°C). During December, the nighttime temperature averages to a freezing cold 23.7°F (-4.6°C).Humidity
The average relative humidity in December is 82%.Rainfall
In Royalston, in December, during 8.8 rainfall days, 2.56" (65mm) of precipitation is typically accumulated. In Royalston, during the entire year, the rain falls for 143.2 days and collects up to 28.7" (729mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Royalston, during December, snow falls for 8.6 days and regularly aggregates up to 5.31" (135mm) of snow. In Royalston, during the entire year, snow falls for 47.7 days and aggregates up to 31.93" (811mm) 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 6:59 am and sunset at 4:16 pm. On the last day of December, sunrise is at 7:18 am and sunset at 4:25 pm EST.
Sunshine
The average sunshine in December is 4.4h.UV index
With an average maximum UV index of 1, December is the month with the lowest UV index. A UV Index value of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A typical high UV index of 1 in December suggests the following recommendations:
Despite most people tolerating extended sun exposure, it is critical to always protect those with sensitive skin, infants, and children. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Be watchful! The reflection of snow can enhance the intensity of the Sun's UV radiation nearly double.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is it in December?
What is the average humidity in December?
How much does it rain in December?
How many days does it snow in December in Royalston?
What is the month with the shortest days?
How many hours of daylight does Royalston have in December?
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
Royalston, MA
- Average high temperature in December: 34.2°F
The warmest month (with the highest average high temperature) is July (79.7°F).
The month with the lowest average high temperature is January (28.8°F).
- Average low temperature in December: 23.7°F
The month with the highest average low temperature is July (59.7°F).
The coldest month (with the lowest average low temperature) is January (16.2°F).
Average pressure in December
Royalston, MA
- Average pressure in December: 30.04"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
Royalston, MA
- Average wind speed in December: 8mph
The windiest months (with the highest average wind speed) are January and February (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in December
Royalston, MA
- Average humidity in December: 82%
The month with the highest relative humidity is February (84%).
The month with the lowest relative humidity is April (74%).
Average rainfall in December
Royalston, MA
- Average rainfall in December: 2.56"
The wettest month (with the highest rainfall) is October (2.95").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Royalston, MA
- Average rainfall days in December: 8.8 days
The months with the highest number of rainy days are May and June (15.4 days).
The month with the least rainy days is January (6.8 days).
Average snowfall in December
Royalston, MA
- Average snowfall in December: 5.31"
The month with the highest snowfall is February (7.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Royalston, MA
- Average snowfall days in December: 8.6 days
The month with the highest number of snowfall days is February (10.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Royalston, MA
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in December: 4h and 2min
The months with the most sunshine are July and August (Average sunshine: 9h and 54min).
The month with the least sunshine is February (Average sunshine: 4h and 6min).
Average sunshine days in December
Royalston, MA
- Average sunshine days in December: 16.8 days
The month with the most sunshine days is November (17.4 days).
The month with the least sunshine days is April (12.7 days).
Average UV index in December
Royalston, MA
- Average UV index in December: 1
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Royalston, MA
- Average cloud cover in December: 52
The months with the most cloud cover are February and March (Cloud cover 53).
The months with the least cloud cover are July and August (Cloud cover 38).
Average visibility in December
Royalston, MA
- Average visibility in December: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).
Royalston, Massachusetts, USA
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