December weather forecastHarrison, NJ
December
Weather in December
The first month of the winter, December, is still a cold month in Harrison, New Jersey, with temperature in the range of an average high of 41.9°F (5.5°C) and an average low of 32.9°F (0.5°C).Temperature
As December commences, the average high-temperature shows a reduction, transitioning from a cool 50.9°F (10.5°C) in November to a cold 41.9°F (5.5°C). December registers an average low temperature of 32.9°F (0.5°C), subtly lower than the daytime maximum.Humidity
The months with the highest humidity are February and December, with an average relative humidity of 75%.Rainfall
In Harrison, in December, during 11.6 rainfall days, 2.95" (75mm) of precipitation is typically accumulated. In Harrison, during the entire year, the rain falls for 150.3 days and collects up to 27.72" (704mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In December, it is snowing for 2.5 days. Throughout December, 1.5" (38mm) of snow is accumulated. In Harrison, during the entire year, snow falls for 18.1 days and aggregates up to 8.46" (215mm) 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 December in Harrison, sunrise is at 7:02 am and sunset at 4:29 pm. On the last day of the month, sunrise is at 7:20 am and sunset at 4:39 pm EST.
Sunshine
In December, the average sunshine is 4.9h.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 minimal health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: The UV index of 2 in December translates into these instructions:
Sun exposure does not present considerable issues for many, yet infants, fair-skinned people, and children necessitate constant protection. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Employ a wide-brim hat for potent defense against up to 50% of UV rays. Take note! UV radiation from the Sun can double in intensity due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Harrison, NJ
- Average high temperature in December: 41.9°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is January (36.3°F).
- Average low temperature in December: 32.9°F
The month with the highest average low temperature is July (69.4°F).
The coldest month (with the lowest average low temperature) is January (25.9°F).
Average pressure in December
Harrison, 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
Harrison, NJ
- Average wind speed in December: 9.4mph
The windiest month (with the highest average wind speed) is January (9.9mph).
The calmest month (with the lowest average wind speed) is July (6.5mph).
Average humidity in December
Harrison, NJ
- Average humidity in December: 75%
The months with the highest relative humidity are February and December (75%).
The month with the lowest relative humidity is August (70%).
Average rainfall in December
Harrison, NJ
- Average rainfall in December: 2.95"
The wettest month (with the highest rainfall) is July (3.23").
The driest months (with the least rainfall) are January and February (1.69").
Average rainfall days in December
Harrison, NJ
- Average rainfall days in December: 11.6 days
The month with the highest number of rainy days is July (17.3 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in December
Harrison, NJ
- Average snowfall in December: 1.5"
The month with the highest snowfall is March (2.8").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Harrison, NJ
- Average snowfall days in December: 2.5 days
The months with the highest number of snowfall days are January and February (5.3 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
Harrison, 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 42min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in December
Harrison, NJ
- Average sunshine days in December: 17.5 days
The month with the most sunshine days is January (19.6 days).
The month with the least sunshine days is July (12 days).
Average UV index in December
Harrison, 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
Harrison, NJ
- Average cloud cover in December: 47
The months with the most cloud cover are February, March and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in December
Harrison, 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).
