December weather forecastSewickley Hills, PA
December
Weather in December
The first month of the winter, December, is also a wintry month in Sewickley Hills, Pennsylvania, with an average temperature fluctuating between 38.7°F (3.7°C) and 28°F (-2.2°C).Temperature
In Sewickley Hills, the beginning of December is marked by a lowered average high-temperature, shifting from November's chilly 48.6°F (9.2°C) to an icy 38.7°F (3.7°C). Sewickley Hills experiences a steady low-temperature of 28°F (-2.2°C) throughout December.Humidity
The average relative humidity in December is 84%.Rainfall
In Sewickley Hills, in December, during 6.6 rainfall days, 0.67" (17mm) of precipitation is typically accumulated. Throughout the year, there are 104.1 rainfall days, and 8.23" (209mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Sewickley Hills, in December, during 6.4 snowfall days, 0.67" (17mm) of snow is typically accumulated. Throughout the year, there are 33.9 snowfall days, and 4.37" (111mm) of snow is accumulated.Daylight
With an average of 9h and 18min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:25 am and sunset at 4:54 pm. On the last day of the month, sunrise is at 7:43 am and sunset at 5:03 pm EST.
Sunshine
The average sunshine in December is 3.2h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for average individuals.Note: The maximum daily UV index of 1 during December translates into the following directions:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. To protect against the Sun's most potent rays, avoid direct exposure around midday. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Notice! The UV radiation of the Sun can be intensified nearly twofold due to the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Sewickley Hills, PA
- Average high temperature in December: 38.7°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (32.5°F).
- Average low temperature in December: 28°F
The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is January (20.1°F).
Average pressure in December
Sewickley Hills, PA
- Average pressure in December: 30.11"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
Sewickley Hills, PA
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is January (8mph).
The calmest months (with the lowest average wind speed) are July and August (4.8mph).
Average humidity in December
Sewickley Hills, PA
- Average humidity in December: 84%
The months with the highest relative humidity are January and February (85%).
The months with the lowest relative humidity are July and August (75%).
Average rainfall in December
Sewickley Hills, PA
- Average rainfall in December: 0.67"
The wettest months (with the highest rainfall) are June and July (0.91").
The driest months (with the least rainfall) are January and November (0.47").
Average rainfall days in December
Sewickley Hills, PA
- Average rainfall days in December: 6.6 days
The month with the highest number of rainy days is May (12.7 days).
The month with the least rainy days is January (4.5 days).
Average snowfall in December
Sewickley Hills, PA
- Average snowfall in December: 0.67"
The month with the highest snowfall is February (1.18").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Sewickley Hills, PA
- Average snowfall days in December: 6.4 days
The month with the highest number of snowfall days is February (9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Sewickley Hills, PA
- Average daylight in December: 9h and 18min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 3h and 12min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 2h and 54min).
Average sunshine days in December
Sewickley Hills, PA
- Average sunshine days in December: 20.5 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is May (14.7 days).
Average UV index in December
Sewickley Hills, PA
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Sewickley Hills, PA
- Average cloud cover in December: 67
The month with the most cloud cover is January (Cloud cover 70).
The month with the least cloud cover is August (Cloud cover 34).
Average visibility in December
Sewickley Hills, PA
- Average visibility in December: 5mi
The months with the highest visibility are April, June, August and November (6mi).
The months with the lowest visibility are January, February, March, May, July, September, October and December (5mi).
