December weather forecastLower Allen, PA
December
Weather in December
December, the first month of the winter in Lower Allen, is also an icy month, with an average temperature fluctuating between 29.8°F (-1.2°C) and 41.2°F (5.1°C).Temperature
The start of December signals a decrease in the average high-temperature, transitioning from a cool 50.2°F (10.1°C) in November to a cold 41.2°F (5.1°C). Lower Allen reports an average nighttime low-temperature of 29.8°F (-1.2°C) in December.Humidity
In Lower Allen, the average relative humidity in December is 79%.Rainfall
In Lower Allen, in December, during 10.5 rainfall days, 1.38" (35mm) of precipitation is typically accumulated. In Lower Allen, during the entire year, the rain falls for 146 days and collects up to 19.53" (496mm) of precipitation.Snowfall
Months with snowfall are January through April, November and December. In Lower Allen, during December, snow falls for 4.5 days and regularly aggregates up to 1.06" (27mm) of snow. Throughout the year, there are 23.2 snowfall days, and 8.39" (213mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of December, sunrise is at 7:11 am and sunset at 4:42 pm. On the last day of the month, sunrise is at 7:29 am and sunset at 4:51 pm EST.
Sunshine
In Lower Allen, the average sunshine in December is 4.7h.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 estimate of 2, and below, represents a low health risk from unsafe exposure to UV radiation for the ordinary person.Note: In December, the maximum UV index of 2 suggests these recommendations:
Babies, children, and individuals with sensitive skin should always have protection against extended sun exposure. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Be prepared! The intensity of the Sun's UV radiation can be amplified nearly double due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Lower Allen, PA
- Average high temperature in December: 41.2°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (35.2°F).
- Average low temperature in December: 29.8°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure in December
Lower Allen, 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
Lower Allen, PA
- Average wind speed in December: 7.8mph
The windiest month (with the highest average wind speed) is March (8.4mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Lower Allen, PA
- Average humidity in December: 79%
The months with the highest relative humidity are February and May (80%).
The month with the lowest relative humidity is April (75%).
Average rainfall in December
Lower Allen, PA
- Average rainfall in December: 1.38"
The wettest months (with the highest rainfall) are May and August (2.09").
The driest months (with the least rainfall) are January and September (1.3").
Average rainfall days in December
Lower Allen, PA
- Average rainfall days in December: 10.5 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in December
Lower Allen, PA
- Average snowfall in December: 1.06"
The month with the highest snowfall is January (2.4").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Lower Allen, PA
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is January (7.1 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Lower Allen, 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 42min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in December
Lower Allen, PA
- Average sunshine days in December: 17.5 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (12 days).
Average UV index in December
Lower Allen, PA
- Average UV index in December: 2
The months with the highest UV index are May, June and 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
Lower Allen, 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 31).
Average visibility in December
Lower Allen, 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).
