December weather forecast
Mount Lebanon, PA

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Weather in December

December, the first month of the winter in Mount Lebanon, is still a cold month, with an average temperature varying between 39.7°F (4.3°C) and 28.4°F (-2°C).

Temperature

Mount Lebanon observes a minor decrease in the average high-temperature with the arrival of December, falling from November's chilly 49.3°F (9.6°C) to a wintry 39.7°F (4.3°C). December witnesses an average low-temperature hovering around a subzero cold 28.4°F (-2°C).

Humidity

In December, the average relative humidity is 83%.

Rainfall

In Mount Lebanon, in December, during 8.2 rainfall days, 0.87" (22mm) of precipitation is typically accumulated. In Mount Lebanon, during the entire year, the rain falls for 132.6 days and collects up to 11.5" (292mm) of precipitation.

Snowfall

January through April, November and December are months with snowfall. In Mount Lebanon, in December, snow falls for 6.4 days, with typically accumulated 0.59" (15mm) of snow. Throughout the year, there are 32.5 snowfall days, and 3.66" (93mm) of snow is accumulated.

Daylight

With an average of 9h and 24min of daylight, December has the shortest days of the year.
On the first day of December, sunrise is at 7:24 am and sunset at 4:54 pm. On the last day of the month, sunrise is at 7:42 am and sunset at 5:04 pm EST.

Sunshine

In December, the average sunshine is 3.4h.

UV index

With an average maximum UV index of 1, December is the month with the lowest UV index. A UV Index value of 2, and less, symbolizes a low health risk from exposure to the Sun's UV rays for ordinary individuals.
Note: During December, 1 as the daily maximum UV index converts into the following advice:
Infants, children, and people with sensitive skin should always have protection against lengthy periods of sun exposure. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. 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. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Updated: Jul 22, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

Is it cold during December?

December temperatures vary between a high-temperature of 39.7°F (4.3°C) and a low-temperature of 28.4°F (-2°C). The average heat index (a.k.a. 'felt air temperature', 'feels like'), which calculates the temperature value influenced by the moisture in the air, in August is evaluated at 87.8°F (31°C).

What is the average humidity in December?

In Mount Lebanon, the average relative humidity in December is 83%.

How much does it rain in December?

In Mount Lebanon, during December, the rain falls for 8.2 days and regularly aggregates up to 0.87" (22mm) of precipitation.

How many days does it snow in December in Mount Lebanon?

In Mount Lebanon, in December, snow falls for 6.4 days, with typically accumulated 0.59" (15mm) of snow.

What is the month with the shortest days?

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

How many hours of daylight does Mount Lebanon have in December?

The average day length in December is 9h and 21min.

What time are sunrise and sunset in December?

On the first day of December, sunrise is at 7:24 am and sunset at 4:54 pm. On the last day of the month, sunrise is at 7:42 am and sunset at 5:04 pm EST.

How many hours of sunshine does Mount Lebanon have in December?

The average sunshine duration in December is 3.4h.

When is the lowest UV index?

The month with the lowest UV index is December, with an average maximum UV index of 1.

What is the UV index reading in December?

In Mount Lebanon, Pennsylvania, the average daily maximum UV index in December is 1. A UV Index reading of 2, and below, represents a low health risk 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
Mount Lebanon, PA

Average temperature in December - Mount Lebanon, PA
  • Average high temperature in December: 39.7°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 (33.4°F).

  • Average low temperature in December: 28.4°F

The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is January (21°F).

Average pressure in December
Mount Lebanon, PA

Average pressure in December - Mount Lebanon, PA
  • Average pressure in December: 30.11"Hg

The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).

Average wind speed in December
Mount Lebanon, PA

Average wind speed in December - Mount Lebanon, PA
  • Average wind speed in December: 7.3mph

The windiest month (with the highest average wind speed) is January (7.9mph).
The calmest months (with the lowest average wind speed) are July and August (4.7mph).

Average humidity in December
Mount Lebanon, PA

Average humidity in December - Mount Lebanon, PA
  • Average humidity in December: 83%

The month with the highest relative humidity is February (85%).
The months with the lowest relative humidity are July and August (75%).

Average rainfall in December
Mount Lebanon, PA

Average rainfall in December - Mount Lebanon, PA
  • Average rainfall in December: 0.87"

The wettest month (with the highest rainfall) is July (1.34").
The driest month (with the least rainfall) is November (0.67").

Average rainfall days in December
Mount Lebanon, PA

Average rainfall days in December - Mount Lebanon, PA
  • Average rainfall days in December: 8.2 days

The month with the highest number of rainy days is July (15.6 days).
The month with the least rainy days is February (6.4 days).

Average snowfall in December
Mount Lebanon, PA

Average snowfall in December - Mount Lebanon, PA
  • Average snowfall in December: 0.59"

The month with the highest snowfall is February (0.98").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in December
Mount Lebanon, PA

Average snowfall days in December - Mount Lebanon, PA
  • Average snowfall days in December: 6.4 days

The month with the highest number of snowfall days is January (9.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Mount Lebanon, PA

Average daylight in December / Average sunshine in December - Mount Lebanon, 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: 3h and 2min

The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 3h and 0min).

Average sunshine days in December
Mount Lebanon, PA

Average sunshine days in December - Mount Lebanon, PA
  • Average sunshine days in December: 18.5 days

The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (12.2 days).

Average UV index in December
Mount Lebanon, PA

Average UV index in December - Mount Lebanon, PA
  • Average UV index in December: 1

The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).

Average cloud cover in December
Mount Lebanon, PA

Average cloud cover in December - Mount Lebanon, PA
  • Average cloud cover in December: 64

The month with the most cloud cover is January (Cloud cover 68).
The month with the least cloud cover is August (Cloud cover 33).

Average visibility in December
Mount Lebanon, PA

Average visibility in December - Mount Lebanon, PA
  • Average visibility in December: 5mi

The months with the highest visibility are April, June, July, August and November (6mi).
The months with the lowest visibility are January, February, March, May, September, October and December (5mi).

Mount Lebanon, Pennsylvania, USA

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