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 average high-temperature decreases in December, shifting from a frosty 43.7°F (6.5°C) in November to a wintry 34.5°F (1.4°C). Westline records an average low-temperature of 24.6°F (-4.1°C) throughout the month of December.Humidity
The average relative humidity in December is 88%.Rainfall
In Westline, in December, during 11.7 rainfall days, 3.15" (80mm) of precipitation is typically accumulated. In Westline, Pennsylvania, during the entire year, the rain falls for 179.4 days and collects up to 35.59" (904mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. In Westline, during December, snow falls for 20.1 days and regularly aggregates up to 11.69" (297mm) of snow. Throughout the year, there are 99.3 snowfall days, and 56.69" (1440mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:23 am and sunset at 4:45 pm. On the last day of the month, sunrise is at 7:42 am and sunset at 4:54 pm EST.
Sunshine
The average sunshine in December is 2.4h.UV index
The months with the lowest UV index are January and December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: A typical high UV index of 1 in December suggests the following recommendations:
Unlike children, who always need sun protection, most individuals can remain in the sun for up to an hour without getting burnt. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Take to heart! Snow reflection can almost magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December in Westline?
How much does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When are sunrise and sunset in December?
How many hours of sunshine does Westline have in December?
When is the lowest UV index?
What is the UV index reading in December?
Average temperature in December
Westline, PA
- Average high temperature in December: 34.5°F
The warmest month (with the highest average high temperature) is July (78.8°F).
The month with the lowest average high temperature is January (28°F).
- Average low temperature in December: 24.6°F
The month with the highest average low temperature is July (56.8°F).
The coldest month (with the lowest average low temperature) is January (16.3°F).
Average pressure in December
Westline, PA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Westline, PA
- Average wind speed in December: 8.5mph
The windiest month (with the highest average wind speed) is January (9.1mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in December
Westline, PA
- Average humidity in December: 88%
The month with the highest relative humidity is February (89%).
The months with the lowest relative humidity are May, June and July (79%).
Average rainfall in December
Westline, PA
- Average rainfall in December: 3.15"
The wettest month (with the highest rainfall) is April (4.09").
The driest month (with the least rainfall) is September (2.24").
Average rainfall days in December
Westline, PA
- Average rainfall days in December: 11.7 days
The month with the highest number of rainy days is May (20.7 days).
The month with the least rainy days is January (8.6 days).
Average snowfall in December
Westline, PA
- Average snowfall in December: 11.69"
The month with the highest snowfall is February (13.66").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Westline, PA
- Average snowfall days in December: 20.1 days
The month with the highest number of snowfall days is January (23.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Westline, PA
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 2h and 2min
The month with the most sunshine is July (Average sunshine: 9h and 36min).
The month with the least sunshine is January (Average sunshine: 2h and 18min).
Average sunshine days in December
Westline, PA
- Average sunshine days in December: 5.1 days
The month with the most sunshine days is September (12.1 days).
The month with the least sunshine days is January (4.5 days).
Average UV index in December
Westline, PA
- Average UV index in December: 1
The months with the highest UV index are May, June, July and August (UV index 5).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in December
Westline, PA
- Average cloud cover in December: 77
The month with the most cloud cover is January (Cloud cover 79).
The months with the least cloud cover are July and August (Cloud cover 42).
Average visibility in December
Westline, PA
- Average visibility in December: 4mi
The months with the highest visibility are March, April, May, June, July, October and November (5mi).
The months with the lowest visibility are January, February, August, September and December (4mi).
Westline, Pennsylvania, USA
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