January weather - Winter 2025

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

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

Weather in January

Moving into January, Bethlehem, Pennsylvania experiences a colder turn in temperatures that provide a fresh chill in the air. January's weather falls on the severe end of the winter scale, with quite high relative humidity percentages at 78% and snowfall inches peaking at 3.23" (82mm). The city's residents will observe fewer daylight hours with gloomy and overcast days becoming commonplace. The month notably has a higher frequency for snowfall days, summing up to 7.8 days in the month. The murky winter weather and chilly statutes are kept at bay with a warm coat, marking the start of a frigid season.

Temperature

January is the month when Bethlehem experiences its coldest temperatures, averaging a high of 34°F (1.1°C) and a low of 21.6°F (-5.8°C).

Humidity

The average relative humidity in January is 78%.

Rainfall

In Bethlehem, during January, the rain falls for 7.8 days and regularly aggregates up to 1.81" (46mm) 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 January, it is snowing for 7.8 days. Throughout January, 3.23" (82mm) of snow is accumulated. Throughout the year, there are 26.7 snowfall days, and 14.49" (368mm) of snow is accumulated.

Daylight

In Bethlehem, the average length of the day in January is 9h and 40min.
On the first day of the month, sunrise is at 7:25 am and sunset at 4:44 pm. On the last day of January, sunrise is at 7:12 am and sunset at 5:17 pm EST.

Sunshine

In Bethlehem, the average sunshine in January 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 of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.
Note: A daily maximum UV index of 2 in January translates into the following instructions:
Extended time in the sun generally does not harm most, but those with sensitive skin, infants, and children should always be protected. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.

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

Frequently asked questions

What are the coldest months?

January is the month when Bethlehem sees the average lowest temperatures, with a high of 34°F (1.1°C) and a low of 21.6°F (-5.8°C).

How cold is January?

In Bethlehem, 34°F (1.1°C) is the average high-temperature and 21.6°F (-5.8°C) is the average low-temperature during January.

What is the average humidity in January in Bethlehem?

The average relative humidity in January is 78%.

How many days does it rain in January?

In Bethlehem, Pennsylvania, in January, during 7.8 rainfall days, 1.81" (46mm) of precipitation is typically accumulated.

How many days does it snow in January?

In Bethlehem, in January, snow falls for 7.8 days, with typically accumulated 3.23" (82mm) of snow.

What is the average length of the day in January?

In January, the average day length is 9h and 40min.

What time are sunrise and sunset in January?

In January, on the first day of the month, sunrise is at 7:25 am and sunset at 4:44 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 5:17 pm EST.

How many hours of sunshine does Bethlehem have in January?

In January, the average sunshine duration is 4.7h.

What is the month with the lowest UV index?

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

What is the UV index reading in January?

In January, the average daily maximum UV index is 2. A UV Index estimate of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation.

Today

Tomorrow

Long-term

Year January F M A M J J A S O N D

Dec

January

Feb

Average high temperature

40.1°F 4.5°C

34°F 1.1°C

37.8°F 3.2°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

8.1mph 13km/h

8.7mph 14km/h

8.5mph 13.7km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average snowfall

Average snowfall days

Average daylight

Average sunshine

Average sunshine days

17.2

13.9

Average UV index

Average cloud cover

Average visibility

Average temperature in January
Bethlehem, PA

Average high temperature in January: 34°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 January: 21.6°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 January
Bethlehem, PA

Average pressure in January: 30.08"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 January
Bethlehem, PA

Average wind speed in January: 8mph

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 January
Bethlehem, PA

Average humidity in January: 78%

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 January
Bethlehem, PA

Average rainfall in January: 1.81"

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 January
Bethlehem, PA

Average rainfall days in January: 7.8 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 January
Bethlehem, PA

Average snowfall in January: 3.23"

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 January
Bethlehem, PA

Average snowfall days in January: 7.8 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 January /
Average sunshine in January
Bethlehem, PA

Average daylight in January: 9h and 4min

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 January: 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 January
Bethlehem, PA

Average sunshine days in January: 18 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 January
Bethlehem, PA

Average UV index in January: 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 January
Bethlehem, PA

Average cloud cover in January: 48

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 January
Bethlehem, PA

Average visibility in January: 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).

January weather forecast
Bethlehem, PA

Contents