December weather forecast and climate
Greendell, NJ

The first month of the winter, December, is also a wintry month in Greendell, New Jersey, with temperature in the range of an average low of 27.3°F (-2.6°C) and an average high of 38.7°F (3.7°C).

Temperature

In December, the average high-temperature decreases, from a frosty 48.4°F (9.1°C) in November, to a wintry 38.7°F (3.7°C). In Greendell, New Jersey, the average low-temperature is 27.3°F (-2.6°C).

Humidity

Months with the highest humidity are February and December, with an average relative humidity of 82%.

Rainfall

In Greendell, in December, during 11.5 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. Throughout the year, in Greendell, there are 161.1 rainfall days, and 28.98" (736mm) of precipitation is accumulated.

Snowfall

January through May, October through December are months with snowfall. In Greendell, during December, snow falls for 6.5 days and regularly aggregates up to 2.83" (72mm) of snow. Throughout the year, there are 36.8 snowfall days, and 17.52" (445mm) of snow is accumulated.

Daylight

The month with the shortest days in Greendell, New Jersey, is December, with an average of 9.3h of daylight.

Sunshine

In December, the average sunshine is 4.6h.

UV index

December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a low health risk from the exposure to the Sun's UV radiation for ordinary individuals.
Note: The average daily UV index of 1 in December transform into the following instructions:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in December in Greendell?

In December, in Greendell, the average high-temperature is 38.7°F (3.7°C), and the average low-temperature is 27.3°F (-2.6°C).

What is the most humid month in Greendell?

February and December, with an average relative humidity of 82%, are most humid months.

What is the average humidity in December in Greendell?

In December, the average relative humidity in Greendell is 82%.

How much does it rain in Greendell in December?

In Greendell, New Jersey, in December, during 11.5 rainfall days, 2.68" (68mm) of precipitation is typically accumulated.

How many days does it snow in December in Greendell?

In December, in Greendell, it is snowing for 6.5 days. Throughout December, 2.83" (72mm) of snow is accumulated.

What is the month with the shortest days in Greendell?

December has the shortest days of the year in Greendell, New Jersey, with an average of 9.3h of daylight.

How many hours of daylight does Greendell have in December?

In Greendell, New Jersey, the average length of the day in December is 9.3h.

How long on average sun shines in December in Greendell?

The average sunshine in December in Greendell is 4.6h.

When is the lowest UV index in Greendell?

December is the month with the lowest UV index in Greendell, with an average maximum UV index of 1.

How high is the UV index in December in Greendell?

The average daily maximum UV index in December in Greendell, New Jersey, is 1. A UV Index reading of 2, and below, represents a low health risk from the exposure to the Sun's UV radiation.
Average temperature in December - Greendell, NJ
  • Average high temperature in December: 3.7°C

The warmest month (with the highest average high temperature) is July (28.2°C).
The month with the lowest average high temperature is January (0.7°C).

  • Average low temperature in December: -2.6°C

The month with the highest average low temperature is July (16.6°C).
The coldest month (with the lowest average low temperature) is January (-6.5°C).

Average pressure in December - Greendell, NJ
  • Average pressure in December: 1018.6mbar

The month with the highest atmospheric pressure is November (1019.7mbar).
The month with the lowest atmospheric pressure is June (1013.7mbar).

Average wind speed in December - Greendell, NJ
  • Average wind speed in December: 11.4km/h

The windiest month (with the highest average wind speed) is March (12.7km/h).
The calmest month (with the lowest average wind speed) is August (7.9km/h).

Average humidity in December - Greendell, NJ
  • Average humidity in December: 82%

Months with the highest relative humidity are February and December (82%).
The month with the lowest relative humidity is April (76%).

Average rainfall in December - Greendell, NJ
  • Average rainfall in December: 68mm

The wettest month (with the highest rainfall) is July (77mm).
The driest month (with the least rainfall) is September (39mm).

Average rainfall days in December - Greendell, NJ
  • Average rainfall days in December: 11.5 days

Months with the highest number of rainy days are May and July (17.3 days).
The month with the least rainy days is January (7.5 days).

Average snowfall in December - Greendell, NJ
  • Average snowfall in December: 72mm

Months with the highest snowfall are January and February (109mm).
Months with the least snowfall are June, July, August and September (0mm).

Average snowfall days in December - Greendell, NJ
  • Average snowfall days in December: 6.5 days

The month with the highest number of snowfall days is January (10.3 days).
Months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December / Average sunshine in December - Greendell, NJ
  • Average daylight in December: 9.3h

The month with the longest days is June (Average daylight: 15.1h).
The month with the shortest days is December (Average daylight: 9.3h).

  • Average sunshine in December: 4.6h

The month with the most sunshine is July (Average sunshine: 10h).
The month with the least sunshine is February (Average sunshine: 4.3h).

Average sunshine days in December - Greendell, NJ
  • Average sunshine days in December: 15.5 days

The month with the most sunshine days is November (17.2 days).
The month with the least sunshine days is June (11.3 days).

Average UV index in December - Greendell, NJ
  • Average UV index in December: 1

The month with the highest UV index is June (UV index 6).
The month with the lowest UV index is December (UV index 1).

Average cloud cover in December - Greendell, NJ
  • Average cloud cover in December: 51

The month with the most cloud cover is February (Cloud cover 52).
Months with the least cloud cover are July and August (Cloud cover 37).

Average visibility in December - Greendell, NJ
  • Average visibility in December: 8km

The month with the highest visibility is April (9km).
Months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (8km).