December weather - Winter 2024

Weather in December
Frequently asked questions
Average temperature in December
Average pressure in December
Average wind speed in December
Average humidity in December
Average rainfall in December
Average rainfall days in December
Average snowfall in December
Average snowfall days in December
Average daylight in December
Average sunshine in December
Average sunshine days in December
Average UV index in December
Average cloud cover in December
Average visibility in December

A tranquil setting of dry trees and neat fields behind this large hall in the Lehigh University in Bethlehem, Pennsylvania

Weather in December

December in Bethlehem indicates the deep plunge into winter, characterized by the mercury's descent to 40.1°F (4.5°C). One of the most prominent instances of cold weather, December boasts of the highest snowfall inches in the second half of the calendar year, falling at 2.48" (63mm). Despite the chill, the city's vitality remains undeterred, celebrating the festive season fervently. Against the backdrop of a wintry canvas, residents indulge in snow activities and outdoor sports. The glistening snow, combined with the magic of the holiday season, creates an enchanting atmosphere, wrapping up the weather cycle on a high note.

Temperature

December brings a decrease in the average high-temperature, shifting from a fresh 50°F (10°C) in November to a wintry 40.1°F (4.5°C). An average low-temperature of 28.8°F (-1.8°C) is noted during the nights in December.

Humidity

In December, the average relative humidity is 80%.

Rainfall

In Bethlehem, during December, the rain falls for 10.7 days and regularly aggregates up to 2.24" (57mm) of precipitation. Throughout the year, there are 153 rainfall days, and 26.81" (681mm) of precipitation is accumulated.

Snowfall

January through May, October through December are months with snowfall. In December, it is snowing for 4.8 days. Throughout December, 2.48" (63mm) of snow is accumulated. In Bethlehem, during the entire year, snow falls for 26.7 days and aggregates up to 14.49" (368mm) of snow.

Daylight

December has the shortest days of the year, with an average of 9h and 18min of daylight.
On the first day of the month, sunrise is at 7:06 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:25 am and sunset at 4:44 pm EST.

Sunshine

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 reading of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for the average person.
Note: In December, a daily maximum UV index of 2 leads to the following instructions:
For the majority, extended sun exposure is not of great concern. Infants and people with sensitive skin must always be protected. Avoiding the Sun's peak radiation during midday hours is essential for health and safety. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Bear in mind! The Sun's UV radiation can nearly double in intensity due to the reflective quality of snow.

Updated: Jun 4, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

Is December cold?

In December, the average high-temperature and low-temperature are 40.1°F (4.5°C) and 28.8°F (-1.8°C) respectively. In August, the average heat index (a.k.a. 'real feel', 'apparent temperature'), which calculates the temperature value influenced by the moisture in the air, is appraised at 86°F (30°C).

What is the average humidity in December?

In December, the average relative humidity is 80%.

How much does it rain in December?

In Bethlehem, in December, during 10.7 rainfall days, 2.24" (57mm) of precipitation is typically accumulated.

How much does it snow in December?

In Bethlehem, in December, during 4.8 snowfall days, 2.48" (63mm) of snow is typically accumulated.

What is the month with the shortest days?

The month with the shortest days is December, with an average of 9h and 18min of daylight.

How many hours of daylight does Bethlehem have in December?

In Bethlehem, the average day length in December is 9h and 19min.

What time are sunrise and sunset in December?

In December, on the first day of the month, sunrise is at 7:06 am and sunset at 4:35 pm. On the last day of the month, sunrise is at 7:25 am and sunset at 4:44 pm EST.

How many hours of sunshine does Bethlehem have in December?

In Bethlehem, the average sunshine duration in December is 4.7h.

What is the month with 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.

How high is the UV index in December?

In Bethlehem, the average daily maximum UV index in December is 2. A UV Index value of 2, and less, symbolizes a low health risk from exposure to the Sun's UV radiation.

Today

Tomorrow

Long-term

Year J F M A M J J A S O N December

Nov

December

Jan

Average high temperature

50°F 10°C

40.1°F 4.5°C

34°F 1.1°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

7.8mph 12.6km/h

8.1mph 13km/h

8.7mph 14km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average snowfall

Average snowfall days

Average daylight

Average sunshine

Average sunshine days

18.9

17.2

Average UV index

Average cloud cover

Average visibility

Average temperature in December
Bethlehem, PA

Average high temperature in December: 40.1°F

The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (34°F).

Average low temperature in December: 28.8°F

The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).

Average pressure in December
Bethlehem, 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
Bethlehem, PA

Average wind speed in December: 7.6mph

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
Bethlehem, PA

Average humidity in December: 80%

The month with the highest relative humidity is February (82%).
The months with the lowest relative humidity are April and July (76%).

Average rainfall in December
Bethlehem, PA

Average rainfall in December: 2.24"

The wettest month (with the highest rainfall) is July (2.91").
The driest month (with the least rainfall) is September (1.57").

Average rainfall days in December
Bethlehem, PA

Average rainfall days in December: 10.7 days

The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is January (7.8 days).

Average snowfall in December
Bethlehem, PA

Average snowfall in December: 2.48"

The month with the highest snowfall is March (4.13").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in December
Bethlehem, PA

Average snowfall days in December: 4.8 days

The months with the highest number of snowfall days are January and February (7.8 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Bethlehem, 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 18min).

Average sunshine in December: 4h and 4min

The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).

Average sunshine days in December
Bethlehem, PA

Average sunshine days in December: 17.2 days

The month with the most sunshine days is November (18.9 days).
The month with the least sunshine days is May (11 days).

Average UV index in December
Bethlehem, 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
Bethlehem, PA

Average cloud cover in December: 50

The month with the most cloud cover is February (Cloud cover 51).
The month with the least cloud cover is July (Cloud cover 34).

Average visibility in December
Bethlehem, PA

Average visibility in December: 5mi

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

December weather forecast
Bethlehem, PA

Contents