December weather forecastAllendale, NJ
December
Weather in December
December, the first month of the winter in Allendale, is also a wintry month, with an average temperature fluctuating between 40.8°F (4.9°C) and 30.4°F (-0.9°C).Temperature
Allendale's average high-temperature decreases in December, falling from a fresh 50.7°F (10.4°C) in November to an icy 40.8°F (4.9°C). In December, the nighttime temperature lowers to an average of 30.4°F (-0.9°C).Humidity
February and December, with an average relative humidity of 78%, are the most humid months in Allendale.Rainfall
The month with the most rainfall is December, when the rain falls for 10.6 days and typically aggregates up to 3.58" (91mm) of precipitation.Snowfall
Months with snowfall are January through April, October through December. In Allendale, in December, during 4.5 snowfall days, 2.05" (52mm) of snow is typically accumulated. Throughout the year, there are 28 snowfall days, and 13.82" (351mm) of snow is accumulated.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 7:02 am and sunset at 4:28 pm. On the last day of December, sunrise is at 7:21 am and sunset at 4:38 pm EST.
Sunshine
In Allendale, the average sunshine in December is 4.7h.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 low health risk from exposure to the Sun's UV radiation for the average person.Note: In December, the average maximum UV index of 2 translates into the following recommendations:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Boost your sun resistance with garments that are densely woven yet spacious. Be attentive! The reflective property of snow can nearly double the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Allendale, NJ
- Average high temperature in December: 40.8°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (35.2°F).
- Average low temperature in December: 30.4°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in December
Allendale, 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
Allendale, NJ
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is March (8mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in December
Allendale, NJ
- Average humidity in December: 78%
The months with the highest relative humidity are February and December (78%).
The month with the lowest relative humidity is August (70%).
Average rainfall in December
Allendale, NJ
- Average rainfall in December: 3.58"
The wettest month (with the highest rainfall) is December (3.58").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days in December
Allendale, NJ
- Average rainfall days in December: 10.6 days
The months with the highest number of rainy days are May and July (16.8 days).
The month with the least rainy days is January (8.4 days).
Average snowfall in December
Allendale, NJ
- Average snowfall in December: 2.05"
The month with the highest snowfall is February (4.09").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Allendale, NJ
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is February (7.9 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Allendale, 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 12min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in December
Allendale, NJ
- Average sunshine days in December: 16.7 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is June (11.5 days).
Average UV index in December
Allendale, 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
Allendale, NJ
- Average cloud cover in December: 49
The month with the most cloud cover is March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in December
Allendale, NJ
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
