December weather forecastAlta Manor, PA
December
Weather in December
The first month of the winter, December, is still a cold month in Alta Manor, Pennsylvania, with an average temperature ranging between min 26.6°F (-3°C) and max 36.9°F (2.7°C).Temperature
The transition into December is accompanied by a temperature decrease, with the average high-temperature shifting from a chilly 46.6°F (8.1°C) in November to a cold 36.9°F (2.7°C). Throughout December, Alta Manor registers a consistent average low-temperature of 26.6°F (-3°C).Humidity
The average relative humidity in December is 84%.Rainfall
In Alta Manor, during December, the rain falls for 12.3 days and regularly aggregates up to 2.17" (55mm) of precipitation. Throughout the year, there are 165 rainfall days, and 25.31" (643mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through May, October through December. In Alta Manor, in December, during 11.1 snowfall days, 3.5" (89mm) of snow is typically accumulated. Throughout the year, there are 58.4 snowfall days, and 20.59" (523mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:18 am and sunset at 4:47 pm. On the last day of the month, sunrise is at 7:36 am and sunset at 4:56 pm EST.
Sunshine
The average sunshine in December is 3.7h.UV index
With an average maximum UV index of 1, December is the month with the lowest UV index in Alta Manor. A UV Index reading of 2, and below, represents a low health risk from exposure to the Sun's UV radiation for the average person.Note: A daily maximum UV index of 1 in December translates into the following instructions:
Extended exposure to the sun should always be avoided by children, infants, and those with sensitive skin. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Alta Manor, PA
- Average high temperature in December: 36.9°F
The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (31.1°F).
- Average low temperature in December: 26.6°F
The month with the highest average low temperature is July (59.4°F).
The coldest month (with the lowest average low temperature) is January (19.4°F).
Average pressure in December
Alta Manor, PA
- Average pressure in December: 30.1"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in December
Alta Manor, PA
- Average wind speed in December: 8.5mph
The windiest month (with the highest average wind speed) is January (9.2mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in December
Alta Manor, PA
- Average humidity in December: 84%
The month with the highest relative humidity is February (85%).
The months with the lowest relative humidity are April and July (77%).
Average rainfall in December
Alta Manor, PA
- Average rainfall in December: 2.17"
The wettest month (with the highest rainfall) is May (2.8").
The driest month (with the least rainfall) is November (1.57").
Average rainfall days in December
Alta Manor, PA
- Average rainfall days in December: 12.3 days
The month with the highest number of rainy days is May (17.9 days).
The month with the least rainy days is February (9.8 days).
Average snowfall in December
Alta Manor, PA
- Average snowfall in December: 3.5"
The month with the highest snowfall is January (5.28").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Alta Manor, PA
- Average snowfall days in December: 11.1 days
The month with the highest number of snowfall days is January (15.9 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Alta Manor, 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 42min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 30min).
Average sunshine days in December
Alta Manor, PA
- Average sunshine days in December: 11.7 days
The month with the most sunshine days is November (15.3 days).
The month with the least sunshine days is February (8.6 days).
Average UV index in December
Alta Manor, PA
- Average UV index in December: 1
The months with the highest UV index are May, June, July and August (UV index 5).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Alta Manor, PA
- Average cloud cover in December: 62
The month with the most cloud cover is January (Cloud cover 65).
The months with the least cloud cover are July and August (Cloud cover 37).
Average visibility in December
Alta Manor, PA
- 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).





