January Weather in Williamsport, United States

Last updated: June 24, 2025

In Williamsport, United States, the average temperature in January hovers around -2°C (29°F), with lows plummeting to -28°C (-18°F) and occasional highs reaching up to 18°C (65°F). Expect a precipitation total of 76 mm (3.0 in) over approximately 8 days throughout the month, accompanied by an average humidity of 85%. Stay warm and prepared for the elements!

January Temperature in Williamsport

In January in Williamsport, the average temperature is -2°C (29°F). Maximum temperatures can reach 18°C (65°F), while the minimum can drop as low as -28°C (-18°F). Travelers should be prepared for a wide temperature range and pack accordingly.

January Weather in Williamsport: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Williamsport, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Williamsport, January typically has an average temperature of -2°C (29°F), with highs reaching up to 18°C (65°F) and lows dropping to around -28°C (-18°F).

Data source: Temperature data for Williamsport generated using information from the Copernicus Climate Change Service.

January Precipitation in Williamsport

In Williamsport in January, the precipitation amount is 76 mm (3.0 in) spread over a duration of 8 days.

January Precipitation Trends in Williamsport

The chart displays monthly precipitation patterns in Williamsport, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Williamsport, January typically receives around 76 mm (3.0 inches) of precipitation spread over approximately 8 days.

Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

January Humidity in Williamsport

In Williamsport in January, humidity is 85%. With an average temperature of -2°C (29°F), this humidity feels like a chilling, damp blanket that clings to your skin, making travel uncomfortable and often prompting an urgent search for warmth and shelter.

January Average Humidity in Williamsport

This chart illustrates the average monthly humidity levels in Williamsport, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Williamsport is approximately 85%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Williamsport

In Williamsport in January, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Williamsport, you can check the information here.

Maximum UV Index Levels in Williamsport for January

The chart shows the monthly maximum UV Index (UVI) for Williamsport in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in Williamsport typically reaches 3, which falls under the moderate exposure category.

Data source: Williamsport January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How January Weather in Williamsport Compares to Other Months

Weather in Williamsport varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Williamsport, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Williamsport, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (29°F)	76 mm (3.0 inches)	85%	moderate
February Weather	0°C (32°F)	77 mm (3.1 inches)	85%	moderate
March Weather	6°C (42°F)	112 mm (4.4 inches)	86%	high
April Weather	11°C (52°F)	104 mm (4.1 inches)	87%	very high
May Weather	18°C (64°F)	151 mm (5.9 inches)	81%	very high
June Weather	23°C (74°F)	103 mm (4.0 inches)	82%	extreme
July Weather	25°C (77°F)	93 mm (3.7 inches)	81%	very high
August Weather	23°C (74°F)	106 mm (4.2 inches)	79%	very high
September Weather	21°C (70°F)	67 mm (2.6 inches)	78%	very high
October Weather	14°C (58°F)	116 mm (4.6 inches)	81%	high
November Weather	5°C (42°F)	76 mm (3.0 inches)	89%	moderate
December Weather	2°C (36°F)	61 mm (2.4 inches)	86%	low