December weather forecastPhiladelphia, NY

December

Weather in December

The first month of the winter, December, is still a freezing cold month in Philadelphia, New York, with an average temperature varying between 22.5°F (-5.3°C) and 31.6°F (-0.2°C).

Temperature

The shift to December brings a decrease in the average high-temperature, falling from a chilly 42.8°F (6°C) in November to a subzero cold 31.6°F (-0.2°C). An average low-temperature of 22.5°F (-5.3°C) marks the month of December in Philadelphia.

Humidity

In December, the average relative humidity is 85%.

Rainfall

In Philadelphia, in December, it is raining for 11.6 days, with typically 2.87" (73mm) of accumulated precipitation. In Philadelphia, during the entire year, the rain falls for 166.4 days and collects up to 30.55" (776mm) of precipitation.

Snowfall

Months with snowfall are January through May, October through December. December is the month with the most snowfall in Philadelphia. Snow falls for 17.4 days and accumulates 9.13" (232mm) of snow.

Daylight

December has the shortest days of the year in Philadelphia, with an average of 8h and 54min of daylight.
On the first day of December in Philadelphia, sunrise is at 7:18 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:37 am and sunset at 4:34 pm EST.

Sunshine

In December, the average sunshine in Philadelphia is 3.2h.

UV index

January and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for the average person.
Note: The maximum daily UV index of 1 in December converts into the following recommendations:
Although the majority can endure up to an hour in the sun without burns, children always require sun protection. To protect against the Sun's most potent rays, avoid direct exposure around midday. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Consider carefully! The reflective quality of 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

In December, the average high-temperature and low-temperature in Philadelphia, New York, are 31.6°F (-0.2°C) and 22.5°F (-5.3°C) respectively.

In December, the average relative humidity in Philadelphia, New York, is 85%.

In Philadelphia, in December, it is raining for 11.6 days, with typically 2.87" (73mm) of accumulated precipitation.

December is the month with the most snowfall in Philadelphia. Snow falls for 17.4 days and accumulates 9.13" (232mm) of snow.

In Philadelphia, New York, during December, snow falls for 17.4 days and regularly aggregates up to 9.13" (232mm) of snow.

The month with the shortest days in Philadelphia is December, with an average of 8h and 54min of daylight.

In Philadelphia, New York, the average day length in December is 8h and 56min.

In December, on the first day of the month, sunrise is at 7:18 am and sunset at 4:25 pm. On the last day of the month, sunrise is at 7:37 am and sunset at 4:34 pm EST.

The average sunshine duration in December in Philadelphia is 3.2h.

The months with the lowest UV index in Philadelphia, New York, are January and December, with an average maximum UV index of 1.

The average daily maximum UV index in December in Philadelphia, New York, is 1. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to UV radiation.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Philadelphia, NY

  • Average high temperature in December: 31.6°F

The warmest month (with the highest average high temperature) is July (76.6°F).
The month with the lowest average high temperature is January (25°F).

  • Average low temperature in December: 22.5°F

The month with the highest average low temperature is July (59.7°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).

Average pressure in December
Philadelphia, NY

  • Average pressure in December: 30.05"Hg

The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in December
Philadelphia, NY

  • Average wind speed in December: 9.2mph

The windiest month (with the highest average wind speed) is January (9.7mph).
The calmest months (with the lowest average wind speed) are July and August (6.6mph).

Average humidity in December
Philadelphia, NY

  • Average humidity in December: 85%

The months with the highest relative humidity are January and February (88%).
The month with the lowest relative humidity is April (77%).

Average rainfall in December
Philadelphia, NY

  • Average rainfall in December: 2.87"

The wettest month (with the highest rainfall) is October (3.39").
The driest month (with the least rainfall) is September (1.77").

Average rainfall days in December
Philadelphia, NY

  • Average rainfall days in December: 11.6 days

The month with the highest number of rainy days is October (17.4 days).
The month with the least rainy days is February (8.1 days).

Average snowfall in December
Philadelphia, NY

  • Average snowfall in December: 9.13"

The month with the highest snowfall is December (9.13").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in December
Philadelphia, NY

  • Average snowfall days in December: 17.4 days

The month with the highest number of snowfall days is January (20.6 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Philadelphia, NY

  • Average daylight in December: 8h and 54min

The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 8h and 54min).

  • Average sunshine in December: 3h and 12min

The months with the most sunshine are July and August (Average sunshine: 10h and 18min).
The months with the least sunshine are January and February (Average sunshine: 2h and 54min).

Average sunshine days in December
Philadelphia, NY

  • Average sunshine days in December: 7.6 days

The month with the most sunshine days is September (14.8 days).
The month with the least sunshine days is February (6.9 days).

Average UV index in December
Philadelphia, NY

  • Average UV index in December: 1

The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).

Average cloud cover in December
Philadelphia, NY

  • Average cloud cover in December: 68

The months with the most cloud cover are January and February (Cloud cover 71).
The month with the least cloud cover is August (Cloud cover 31).

Average visibility in December
Philadelphia, NY

  • Average visibility in December: 5mi

The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).