December weather forecast
Delaware, NJ

Share

Weather in December

The first month of the winter, December, is still a cold month in Delaware, New Jersey, with an average temperature ranging between min 26.8°F (-2.9°C) and max 38.3°F (3.5°C).

Temperature

Delaware's progression into December includes a drop in the average high-temperature, from a frosty 47.8°F (8.8°C) in November to a cold 38.3°F (3.5°C). In the month of December, Delaware experiences an average low-temperature of 26.8°F (-2.9°C).

Humidity

The months with the highest humidity in Delaware are February, October and December, with an average relative humidity of 82%.

Rainfall

In Delaware, New Jersey, during December, the rain falls for 12.6 days and regularly aggregates up to 3.03" (77mm) of precipitation. Throughout the year, in Delaware, there are 165.9 rainfall days, and 31.61" (803mm) of precipitation is accumulated.

Snowfall

January through May, October through December are months with snowfall in Delaware, New Jersey. In Delaware, during December, snow falls for 7.5 days and regularly aggregates up to 3.39" (86mm) of snow. Throughout the year, in Delaware, there are 42.7 snowfall days, and 21.26" (540mm) of snow is accumulated.

Daylight

With an average of 9h and 18min of daylight, December has the shortest days of the year in Delaware.
On the first day of the month, sunrise is at 7:06 am and sunset at 4:33 pm. On the last day of December, sunrise is at 7:24 am and sunset at 4:42 pm EST.

Sunshine

The average sunshine in December in Delaware is 4.7h.

UV index

With an average maximum UV index of 1, December is the month with the lowest UV index in Delaware. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from exposure to the Sun's UV rays for the ordinary person.
Note: The daily high UV index of 1 during December translates into the following recommendations:
While most individuals can withstand prolonged sun exposure, it is imperative that babies, children, and those with sensitive skin always be shielded. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Consider this! The reflection from snow can almost double the intensity of the Sun's UV radiation.
Updated: Feb 13, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How cold is it in Delaware in December?

In Delaware, in December, the average high-temperature is 38.3°F (3.5°C), and the average low-temperature is 26.8°F (-2.9°C). The average heat index (a.k.a. 'felt air temperature', 'real feel'), which represents the influence of relative humidity on air temperature, in July is evaluated at 87.8°F (31°C).

What is the most humid month in Delaware?

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

What is the average humidity in December in Delaware?

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

How much does it rain in Delaware in December?

In Delaware, in December, during 12.6 rainfall days, 3.03" (77mm) of precipitation is typically accumulated.

How much does it snow in Delaware in December?

In Delaware, New Jersey, during December, snow falls for 7.5 days and regularly aggregates up to 3.39" (86mm) of snow.

What is the month with the shortest days in Delaware?

December has the shortest days of the year in Delaware, with an average of 9h and 18min of daylight.

How many hours of daylight does Delaware have in December?

The average day length in December in Delaware, New Jersey, is 9h and 18min.

When is the sunrise / sunset in December in Delaware?

In December, on the first day of the month, sunrise is at 7:06 am and sunset at 4:33 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 4:42 pm EST.

How many hours of sunshine does Delaware have in December?

The average sunshine duration in December in Delaware is 4.7h.

What is the month with the lowest UV index in Delaware?

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

What is the UV index reading in December in Delaware?

In Delaware, New Jersey, the average daily maximum UV index in December is 1. A UV Index reading of 2, and below, represents a low health threat from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Delaware, NJ

Average temperature in December - Delaware, NJ
  • Average high temperature in December: 38.3°F

The warmest month (with the highest average high temperature) is July (82.2°F).
The month with the lowest average high temperature is January (32.5°F).

  • Average low temperature in December: 26.8°F

The month with the highest average low temperature is July (61.2°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).

Average pressure in December
Delaware, NJ

Average pressure in December - Delaware, 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
Delaware, NJ

Average wind speed in December - Delaware, NJ
  • Average wind speed in December: 7.1mph

The windiest months (with the highest average wind speed) are January, February and March (7.8mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).

Average humidity in December
Delaware, NJ

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

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

Average rainfall in December
Delaware, NJ

Average rainfall in December - Delaware, NJ
  • Average rainfall in December: 3.03"

The wettest month (with the highest rainfall) is July (3.11").
The driest month (with the least rainfall) is September (1.81").

Average rainfall days in December
Delaware, NJ

Average rainfall days in December - Delaware, NJ
  • Average rainfall days in December: 12.6 days

The month with the highest number of rainy days is July (17.4 days).
The month with the least rainy days is February (9.5 days).

Average snowfall in December
Delaware, NJ

Average snowfall in December - Delaware, NJ
  • Average snowfall in December: 3.39"

The month with the highest snowfall is February (5.67").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in December
Delaware, NJ

Average snowfall days in December - Delaware, NJ
  • Average snowfall days in December: 7.5 days

The month with the highest number of snowfall days is January (11.4 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Delaware, NJ

Average daylight in December / Average sunshine in December - Delaware, NJ
  • Average daylight in December: 9h and 2min

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 4min

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 18min).

Average sunshine days in December
Delaware, NJ

Average sunshine days in December - Delaware, NJ
  • Average sunshine days in December: 14.5 days

The month with the most sunshine days is November (16.4 days).
The month with the least sunshine days is June (11.1 days).

Average UV index in December
Delaware, NJ

Average UV index in December - Delaware, 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
Delaware, NJ

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

The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 35).

Average visibility in December
Delaware, NJ

Average visibility in December - Delaware, NJ
  • Average visibility in December: 5mi

The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).

Delaware, New Jersey, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location