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 shift from November to December involves a decrease in the average high-temperature, dropping from a cool 53.2°F (11.8°C) to a chilly 44.1°F (6.7°C). December brings an average low-temperature of 32.9°F (0.5°C) to Mount Royal.Humidity
The months with the highest humidity are October and December, with an average relative humidity of 77%.Rainfall
In Mount Royal, during December, the rain falls for 7.1 days and regularly aggregates up to 0.91" (23mm) of precipitation. Throughout the year, there are 113.4 rainfall days, and 9.25" (235mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 1.7 days. Throughout December, 0.12" (3mm) of snow is accumulated. Throughout the year, there are 10.9 snowfall days, and 1.65" (42mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of December, sunrise is at 7:03 am and sunset at 4:36 pm. On the last day of the month, sunrise is at 7:21 am and sunset at 4:46 pm EST.
Sunshine
The average sunshine in December is 5.1h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for the average person.Note: The maximum UV index of 2 during December translates into these guidelines:
The majority are not significantly affected by prolonged sun exposure. Infants, children, and those with fair skin must always have protection. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is it cold during December?
What is the most humid month?
What is the average humidity in December?
How many days does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When is the sunrise / sunset in December?
How many hours of sunshine does Mount Royal have in December?
What is the month with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Mount Royal, NJ
- Average high temperature in December: 44.1°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.9°F).
- Average low temperature in December: 32.9°F
The month with the highest average low temperature is July (69.1°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in December
Mount Royal, NJ
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Mount Royal, NJ
- Average wind speed in December: 7.8mph
The windiest months (with the highest average wind speed) are March and April (8.6mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in December
Mount Royal, NJ
- Average humidity in December: 77%
The months with the highest relative humidity are October and December (77%).
The month with the lowest relative humidity is April (71%).
Average rainfall in December
Mount Royal, NJ
- Average rainfall in December: 0.91"
The wettest month (with the highest rainfall) is August (1.1").
The driest month (with the least rainfall) is January (0.51").
Average rainfall days in December
Mount Royal, NJ
- Average rainfall days in December: 7.1 days
The month with the highest number of rainy days is July (13.2 days).
The month with the least rainy days is November (6.3 days).
Average snowfall in December
Mount Royal, NJ
- Average snowfall in December: 0.12"
The month with the highest snowfall is February (0.59").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Mount Royal, NJ
- Average snowfall days in December: 1.7 days
The month with the highest number of snowfall days is January (3.5 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Mount Royal, NJ
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 5h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 54min).
Average sunshine days in December
Mount Royal, NJ
- Average sunshine days in December: 22 days
The month with the most sunshine days is November (22.5 days).
The month with the least sunshine days is July (14.7 days).
Average UV index in December
Mount Royal, NJ
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Mount Royal, NJ
- Average cloud cover in December: 45
The months with the most cloud cover are February and March (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 29).
Average visibility in December
Mount Royal, NJ
- 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).
Mount Royal, New Jersey, USA
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