December weather forecastMountainville, NJ
December
Weather in December
December, the first month of the winter in Mountainville, is still a cold month, with an average temperature fluctuating between 29.3°F (-1.5°C) and 41°F (5°C).Temperature
As Mountainville, New Jersey, enters December, the average high-temperature decreases from the a cool 50.4°F (10.2°C) of November to an icy 41°F (5°C). The mean low-temperature during December nights is a freezing cold 29.3°F (-1.5°C).Humidity
February, October and December, with an average relative humidity of 80%, are the most humid months.Rainfall
The month with the most rainfall is December, when the rain falls for 12.3 days and typically aggregates up to 3.35" (85mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In Mountainville, in December, snow falls for 4 days, with typically accumulated 2.32" (59mm) of snow. In Mountainville, during the entire year, snow falls for 27.8 days and aggregates up to 15.35" (390mm) of snow.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:04 am and sunset at 4:32 pm. On the last day of December, sunrise is at 7:23 am and sunset at 4:42 pm EST.
Sunshine
In December, the average sunshine in Mountainville is 4.9h.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 of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: An average maximum UV index of 2 in December leads to these recommendations:
Infants, children, and people with sensitive skin should always have protection against lengthy periods of sun exposure. Direct Sun exposure should be minimized especially during midday when radiation is most intense. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Beware! Reflection from snow can magnify the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Mountainville, NJ
- Average high temperature in December: 41°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (35.1°F).
- Average low temperature in December: 29.3°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure in December
Mountainville, NJ
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Mountainville, NJ
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Mountainville, NJ
- Average humidity in December: 80%
The months with the highest relative humidity are February, October and December (80%).
The month with the lowest relative humidity is April (75%).
Average rainfall in December
Mountainville, NJ
- Average rainfall in December: 3.35"
The wettest month (with the highest rainfall) is December (3.35").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Mountainville, NJ
- Average rainfall days in December: 12.3 days
The month with the highest number of rainy days is July (17.6 days).
The month with the least rainy days is January (8.8 days).
Average snowfall in December
Mountainville, NJ
- Average snowfall in December: 2.32"
The month with the highest snowfall is March (4.76").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Mountainville, NJ
- Average snowfall days in December: 4 days
The months with the highest number of snowfall days are January and February (8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Mountainville, NJ
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 4h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Mountainville, NJ
- Average sunshine days in December: 16.2 days
The month with the most sunshine days is November (17.5 days).
The month with the least sunshine days is June (11 days).
Average UV index in December
Mountainville, NJ
- 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
Mountainville, NJ
- Average cloud cover in December: 49
The months with the most cloud cover are February and December (Cloud cover 49).
The months with the least cloud cover are July and August (Cloud cover 34).
Average visibility in December
Mountainville, NJ
- Average visibility in December: 6mi
The months with the highest visibility are January, March, April, June, July, November and December (6mi).
The months with the lowest visibility are February, May, August, September and October (5mi).
