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
A shift in the average high-temperature occurs in December, reducing from a chilly 48.2°F (9°C) in November to an icy 38.8°F (3.8°C). Throughout December, Northumberland witnesses a consistent average low-temperature of 28°F (-2.2°C).Humidity
In Northumberland, the average relative humidity in December is 81%.Rainfall
In December, the rain falls for 9.4 days. Throughout December, 0.87" (22mm) of precipitation is accumulated. Throughout the year, there are 133.4 rainfall days, and 13.15" (334mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, November and December. In Northumberland, in December, during 6.1 snowfall days, 0.59" (15mm) of snow is typically accumulated. In Northumberland, during the entire year, snow falls for 32.1 days and aggregates up to 4.76" (121mm) 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 the month, sunrise is at 7:12 am and sunset at 4:39 pm. On the last day of December, sunrise is at 7:31 am and sunset at 4:49 pm EST.
Sunshine
In December, the average sunshine is 4.4h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Northumberland. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for the ordinary person.Note: In December, a daily UV index of 2 turns into the following recommendations:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. A hat with a broad brim is indispensable, filtering out up to half of UV rays. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is December cold?
What is the average humidity in December?
How much does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Northumberland have in December?
When are sunrise and sunset in December?
How long on average sun shines in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Northumberland, PA
- Average high temperature in December: 38.8°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 (32.2°F).
- Average low temperature in December: 28°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 (20.1°F).
Average pressure in December
Northumberland, PA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Northumberland, PA
- Average wind speed in December: 7.1mph
The windiest month (with the highest average wind speed) is April (7.9mph).
The calmest month (with the lowest average wind speed) is August (4.6mph).
Average humidity in December
Northumberland, PA
- Average humidity in December: 81%
The month with the highest relative humidity is February (82%).
The months with the lowest relative humidity are March and April (76%).
Average rainfall in December
Northumberland, PA
- Average rainfall in December: 0.87"
The wettest month (with the highest rainfall) is July (1.65").
The driest month (with the least rainfall) is September (0.75").
Average rainfall days in December
Northumberland, PA
- Average rainfall days in December: 9.4 days
The month with the highest number of rainy days is May (14.7 days).
The month with the least rainy days is January (7.7 days).
Average snowfall in December
Northumberland, PA
- Average snowfall in December: 0.59"
The month with the highest snowfall is February (1.46").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Northumberland, PA
- Average snowfall days in December: 6.1 days
The month with the highest number of snowfall days is January (9.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Northumberland, PA
- 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 2min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 12min).
Average sunshine days in December
Northumberland, PA
- Average sunshine days in December: 17.8 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is April (13.4 days).
Average UV index in December
Northumberland, PA
- Average UV index in December: 2
The month with the highest UV index is July (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
Northumberland, PA
- Average cloud cover in December: 54
The months with the most cloud cover are February and December (Cloud cover 54).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in December
Northumberland, PA
- Average visibility in December: 6mi
The months with the highest visibility are March, April, November and December (6mi).
The months with the lowest visibility are January, February, May, June, July, August, September and October (5mi).
Northumberland, Pennsylvania, USA
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