December weather forecastSumneytown, PA
December
Weather in December
December, the first month of the winter in Sumneytown, is also a wintry month, with an average temperature fluctuating between 41.5°F (5.3°C) and 30.4°F (-0.9°C).Temperature
As December commences, the average high-temperature shows a reduction, transitioning from a cool 50.9°F (10.5°C) in November to a cold 41.5°F (5.3°C). The mean low-temperature during December nights is a subzero cold 30.4°F (-0.9°C).Humidity
In Sumneytown, the average relative humidity in December is 80%.Rainfall
In December, the rain falls for 8 days. Throughout December, 1.34" (34mm) of precipitation is accumulated. Throughout the year, there are 128.6 rainfall days, and 15.16" (385mm) of precipitation is accumulated.Snowfall
January through May, November and December are months with snowfall. In Sumneytown, in December, during 2 snowfall days, 1.34" (34mm) of snow is typically accumulated. In Sumneytown, during the entire year, snow falls for 17 days and aggregates up to 5.43" (138mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 24min of daylight.On the first day of December, sunrise is at 7:05 am and sunset at 4:36 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 4:45 pm EST.
Sunshine
The average sunshine in December is 4.8h.UV index
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index reading of 2, and below, represents a low health risk from unsafe exposure to UV radiation for average individuals.Note: The maximum UV index, 2 during December, leads to the following recommendations:
In contrast to children, who must always be shielded from the sun, most people can tolerate up to an hour of sun exposure without any burns. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation. Be attentive! The reflective property of snow can nearly double the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Sumneytown, PA
- Average high temperature in December: 41.5°F
The warmest month (with the highest average high temperature) is July (84.6°F).
The month with the lowest average high temperature is January (35.2°F).
- Average low temperature in December: 30.4°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in December
Sumneytown, PA
- Average pressure in December: 30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in December
Sumneytown, PA
- Average wind speed in December: 7.5mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in December
Sumneytown, PA
- Average humidity in December: 80%
The month with the highest relative humidity is February (81%).
The months with the lowest relative humidity are April and July (75%).
Average rainfall in December
Sumneytown, PA
- Average rainfall in December: 1.34"
The wettest month (with the highest rainfall) is July (1.97").
The driest month (with the least rainfall) is January (0.87").
Average rainfall days in December
Sumneytown, PA
- Average rainfall days in December: 8 days
The month with the highest number of rainy days is July (15.7 days).
The month with the least rainy days is January (5.7 days).
Average snowfall in December
Sumneytown, PA
- Average snowfall in December: 1.34"
The month with the highest snowfall is March (1.46").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in December
Sumneytown, PA
- Average snowfall days in December: 2 days
The month with the highest number of snowfall days is February (5.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Sumneytown, PA
- Average daylight in December: 9h and 24min
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 24min).
- Average sunshine in December: 4h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in December
Sumneytown, PA
- Average sunshine days in December: 20.1 days
The month with the most sunshine days is November (21.4 days).
The month with the least sunshine days is July (12.8 days).
Average UV index in December
Sumneytown, PA
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (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
Sumneytown, PA
- Average cloud cover in December: 49
The month with the most cloud cover is February (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in December
Sumneytown, PA
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).





