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 arrival of December corresponds with a light shift in temperature, down from a fresh 52.2°F (11.2°C) in November to a chilly 43.3°F (6.3°C). December witnesses an average nighttime temperature of 32.7°F (0.4°C) in South River.Humidity
February, May, October and December, with an average relative humidity of 77%, are the most humid months.Rainfall
In South River, in December, it is raining for 10.6 days, with typically 3.11" (79mm) of accumulated precipitation. In South River, during the entire year, the rain falls for 154 days and collects up to 30.75" (781mm) of precipitation.Snowfall
Months with snowfall in South River are January through April, November and December. In South River, in December, snow falls for 3.1 days, with typically accumulated 1.02" (26mm) of snow. In South River, during the entire year, snow falls for 18.1 days and aggregates up to 8.35" (212mm) of snow.Daylight
December has the shortest days of the year in South River, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:02 am and sunset at 4:31 pm. On the last day of December, sunrise is at 7:20 am and sunset at 4:41 pm EST.
Sunshine
In South River, New Jersey, the average sunshine in December 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 reading of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In December, a regular UV index of 2 translates into these guidelines:
While most people are not greatly affected by extended sun exposure, those with fair skin, babies, and children must always have protection. It's recommended to limit sun exposure when its radiation is at its peak during midday. For excellent sun protection for the eyes, ears, face, and neck, consider a wide-brim hat. Consider this! The reflection from snow can almost double the intensity of the Sun's UV radiation.
Frequently asked questions
How cold is it in South River in December?
What are the most humid months in South River?
What is the average humidity in December in South River?
How much does it rain in South River in December?
How much does it snow in South River in December?
What is the month with the shortest days in South River?
How many hours of daylight does South River have in December?
When are sunrise and sunset in December in South River?
How long on average sun shines in December in South River?
When is the lowest UV index in South River?
What is the UV index reading in December in South River?
Average temperature in December
South River, NJ
- Average high temperature in December: 43.3°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (36.9°F).
- Average low temperature in December: 32.7°F
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in December
South River, NJ
- Average pressure in December: 30.08"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
South River, NJ
- Average wind speed in December: 8.9mph
The windiest months (with the highest average wind speed) are January and March (9.6mph).
The calmest month (with the lowest average wind speed) is July (6.2mph).
Average humidity in December
South River, NJ
- Average humidity in December: 77%
The months with the highest relative humidity are February, May, October and December (77%).
The months with the lowest relative humidity are April and August (73%).
Average rainfall in December
South River, NJ
- Average rainfall in December: 3.11"
The wettest month (with the highest rainfall) is July (3.58").
The driest month (with the least rainfall) is September (1.81").
Average rainfall days in December
South River, NJ
- Average rainfall days in December: 10.6 days
The month with the highest number of rainy days is July (17.4 days).
The months with the least rainy days are January and November (8.5 days).
Average snowfall in December
South River, NJ
- Average snowfall in December: 1.02"
The month with the highest snowfall is March (3.82").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
South River, NJ
- Average snowfall days in December: 3.1 days
The month with the highest number of snowfall days is February (5.1 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
South River, NJ
- Average daylight in December: 9h and 2min
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 5min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days in December
South River, NJ
- Average sunshine days in December: 18 days
The month with the most sunshine days is November (20 days).
The month with the least sunshine days is July (10.5 days).
Average UV index in December
South River, 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, March, November and December (UV index 2).
Average cloud cover in December
South River, NJ
- Average cloud cover in December: 48
The months with the most cloud cover are February and December (Cloud cover 48).
The months with the least cloud cover are July and August (Cloud cover 31).
Average visibility in December
South River, 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).
South River, New Jersey, USA
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