December weather forecast
Lower Allen, PA

Share

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.
Updated: Jul 20, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How cold is it in December?

In December, the average high-temperature and low-temperature are 41.2°F (5.1°C) and 29.8°F (-1.2°C) respectively. The average heat index (a.k.a. 'apparent temperature', 'feels like'), which combines relative humidity and air temperature, in August is estimated at 86°F (30°C).

What is the average humidity in December?

In Lower Allen, the average relative humidity in December is 79%.

How much does it rain in December?

In Lower Allen, in December, during 10.5 rainfall days, 1.38" (35mm) of precipitation is typically accumulated.

How many days does it snow in December?

In Lower Allen, during December, snow falls for 4.5 days and regularly aggregates up to 1.06" (27mm) of snow.

What is the month with the shortest days in Lower Allen?

With an average of 9h and 24min of daylight, December has the shortest days of the year.

What is the average length of the day in December?

In December, the average day length in Lower Allen, Pennsylvania, is 9h and 22min.

What time are sunrise and sunset in December?

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.

How many hours of sunshine does Lower Allen have in December?

The average sunshine duration in December is 4.7h.

When is the lowest UV index?

The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2.

What is the UV index intensity in December?

In Lower Allen, the average daily maximum UV index in December is 2. A UV Index estimate of 2, and below, represents a low health threat from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Lower Allen, PA

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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 / Average sunshine in December - Lower Allen, PA
  • Average daylight in December: 9h and 2min

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 4min

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 - 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 - 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 - 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 - 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).

Lower Allen, Pennsylvania, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location