December weather forecastDemarest, NJ
December
Weather in December
December, the first month of the winter in Demarest, is also an icy month, with an average temperature ranging between max 41.7°F (5.4°C) and min 30.9°F (-0.6°C).Temperature
With the beginning of December, the average high-temperature shows a decrease, transitioning from a cool 50.9°F (10.5°C) in November to an icy 41.7°F (5.4°C). December nights experience a consistent temperature drop to a subzero cold 30.9°F (-0.6°C).Humidity
In December, the average relative humidity is 76%.Rainfall
The month with the most rainfall in Demarest is December, when the rain falls for 10.7 days and typically aggregates up to 3.46" (88mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Demarest, in December, during 4.6 snowfall days, 1.93" (49mm) of snow is typically accumulated. In Demarest, during the entire year, snow falls for 25.5 days and aggregates up to 10.55" (268mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:01 am and sunset at 4:28 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 4:37 pm EST.
Sunshine
The average sunshine in December is 4.7h.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 reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for average individuals.Note: The daily high UV index of 2 during December translates into the following recommendations:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Heads up! The UV radiation from the Sun can almost be doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Demarest, NJ
- Average high temperature in December: 41.7°F
The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in December: 30.9°F
The month with the highest average low temperature is July (68°F).
The coldest month (with the lowest average low temperature) is January (24.1°F).
Average pressure in December
Demarest, NJ
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Demarest, NJ
- Average wind speed in December: 8mph
The windiest months (with the highest average wind speed) are January and March (8.5mph).
The calmest months (with the lowest average wind speed) are July and August (5.8mph).
Average humidity in December
Demarest, NJ
- Average humidity in December: 76%
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is August (68%).
Average rainfall in December
Demarest, NJ
- Average rainfall in December: 3.46"
The wettest month (with the highest rainfall) is December (3.46").
The driest month (with the least rainfall) is September (1.73").
Average rainfall days in December
Demarest, NJ
- Average rainfall days in December: 10.7 days
The month with the highest number of rainy days is May (16.8 days).
The month with the least rainy days is January (8.2 days).
Average snowfall in December
Demarest, NJ
- Average snowfall in December: 1.93"
The month with the highest snowfall is March (3.07").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Demarest, NJ
- Average snowfall days in December: 4.6 days
The month with the highest number of snowfall days is January (6.9 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
Demarest, NJ
- Average daylight in December: 9h and 18min
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 18min).
- Average sunshine in December: 4h and 42min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Demarest, NJ
- Average sunshine days in December: 16.8 days
The months with the most sunshine days are January and November (18.1 days).
The months with the least sunshine days are April and June (12.7 days).
Average UV index in December
Demarest, 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
Demarest, NJ
- Average cloud cover in December: 49
The months with the most cloud cover are February, March and December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 32).
Average visibility in December
Demarest, 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).
