Allentown
Pennsylvania, USA
Long-term weather forecast
Long-term weather forecast

December weather forecast and climate
Allentown, PA

An aerial view of the vast city of Allentown in Pennsylvania, on a hot, sunny day, with the partly cloudy sky and a far view of a clear horizon line
An aerial view of the vast city of Allentown in Pennsylvania, on a hot, sunny day, with the partly cloudy sky and a far view of a clear horizon line
Diciembre, the first month of the winter, in Allentown, is also a wintry month, with temperature in the range of an average high of 40.5°F (4.7°C) and an average low of 24.1°F (-4.4°C).

Temperature

In Diciembre, the average high-temperature decreases, from a fresh 52.5°F (11.4°C) in Noviembre, to a cold 40.5°F (4.7°C). The average low-temperature, in Diciembre, is 24.1°F (-4.4°C).

Humidity

In Allentown, Pennsylvania, the average relative humidity in Diciembre is 71.4%.

Rainfall

In Allentown, during Diciembre, the rain falls for 10.9 days and regularly aggregates up to 3.58" (90.9mm) of precipitation. Throughout the year, in Allentown, there are 126.8 rainfall days, and 45.35" (1151.9mm) of precipitation is accumulated.

Snowfall

Months with snowfall in Allentown are Enero through Abril, Noviembre and Diciembre. In Allentown, during Diciembre, snow falls for 3.5 days and regularly aggregates up to 5.2" (132.1mm) of snow. In Allentown, during the entire year, snow falls for 17.4 days, and aggregates up to 32.9" (835.7mm) of snow.

Daylight

The month with the shortest days is Diciembre, with an average of 9.3h of daylight.

Sunshine

Noviembre and Diciembre, with an average of 4h of sunshine, are months with the least sunshine.

UV index

Diciembre is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to the UV radiation for the ordinary person.
Note: In Diciembre, the average maximum UV index of 1 translate into the following recommendations:
People with sensitive skin, children, and babies should always be protected from prolonged sun exposure. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in Diciembre in Allentown?

The average high-temperature, in Diciembre, is 40.5°F (4.7°C), while the average low-temperature is 24.1°F (-4.4°C).

What is the average humidity in Diciembre in Allentown?

The average relative humidity in Diciembre is 71.4%.

How many days does it rain in Diciembre in Allentown?

In Diciembre, in Allentown, the rain falls for 10.9 days. Throughout Diciembre, 3.58" (90.9mm) of precipitation is accumulated.

How many days does it snow in Diciembre in Allentown?

In Allentown, Pennsylvania, in Diciembre, during 3.5 snowfall days, 5.2" (132.1mm) of snow is typically accumulated.

What is the month with the shortest days in Allentown?

The month with the shortest days is Diciembre, with an average of 9.3h of daylight.

How many hours of daylight does Allentown have in Diciembre?

In Allentown, the average length of the day in Diciembre is 9.3h.

What is the month with the least sunshine in Allentown?

Noviembre and Diciembre, with an average of 4h of sunshine, are months with the least sunshine in Allentown, Pennsylvania.

How many hours of sunshine does Allentown have in Diciembre?

The average sunshine in Diciembre in Allentown, Pennsylvania, is 4h.

What is the month with the lowest UV index in Allentown?

The month with the lowest UV index in Allentown is Diciembre, with an average maximum UV index of 1.

What is the UV index intensity in Diciembre in Allentown?

In Allentown, the average daily maximum UV index in Diciembre is 1. A UV Index value of 2, and less, symbolizes a low health threat from the exposure to the Sun's UV radiation.
Average temperature in December - Allentown, PA
  • Average high temperature in December: 40.5°F

The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (36°F).

  • Average low temperature in December: 24°F

The month with the highest average low temperature is July (62.7°F).
The coldest month (with the lowest average low temperature) is January (19.5°F).

Average humidity in December - Allentown, PA
  • Average humidity in December: 71.4%

The month with the highest relative humidity is September (74%).
The month with the lowest relative humidity is April (60.9%).

Average rainfall in December - Allentown, PA
  • Average rainfall in December: 3.6"

The wettest month (with the highest rainfall) is July (5").
The driest month (with the lowest rainfall) is February (2.7").

Average rainfall days in December - Allentown, PA
  • Average rainfall days in December: 10.9 days

Months with the highest number of rainy days are April and May (12.1 days).
Months with the lowest number of rainy days are September and October (9.1 days).

Average snowfall in December - Allentown, PA
  • Average snowfall in December: 5.2"

The month with the highest snowfall is February (11.1").
Months with the lowest snowfall are May, June, July, August, September and October (0").

Average snowfall days in December - Allentown, PA
  • Average snowfall days in December: 3.5 days

The month with the highest number of snowfall days is January (5.6 days).
Months with the lowest number of snowfall days are May, June, July, August, September and October (0 days).

Average daylight in December / Average sunshine in December - Allentown, PA
  • Average daylight in December: 9.3h

The month with the longest days is June (Average daylight: 15h).
The month with shortest days is December (Average daylight: 9.3h).

  • Average sunshine in December: 4h

Months with most sunshine are June and July (Average sunshine: 9h).
Months with least sunshine are November and December (Average sunshine: 4).

Average UV index in December - Allentown, PA
  • Average UV index in December: 1

Months with the highest UV index are June and July (UV index 9).
The month with the lowest UV index is December (UV index 1).