January Weather in Harrisburg, United States

Last updated: June 24, 2025

In January, the average temperature in Harrisburg, United States hovers around 5°C (41°F), making it a brisk time of year. Temperatures can vary significantly, with minimums plummeting to -14°C (7°F) and maximums reaching up to 23°C (73°F). Visitors should be prepared for wet weather, as precipitation averages around 100 mm (3.9 in) over 9 days. Additionally, the air is quite humid, with an average humidity level of 84%.

January Temperature in Harrisburg

In January in Harrisburg, the average temperature is 5°C (41°F). Maximums can reach 23°C (73°F), while minimums can drop as low as -14°C (7°F). Be prepared for a wide range of temperatures when traveling during this time.

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

The chart illustrates January temperature patterns in Harrisburg, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Harrisburg, January typically has an average temperature of 5°C (41°F), with highs reaching up to 23°C (73°F) and lows dropping to around -14°C (7°F).

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

January Precipitation in Harrisburg

In Harrisburg in January, the precipitation amount is 100 mm (3.9 in) spread over 9 days.

January Precipitation Trends in Harrisburg

The chart displays monthly precipitation patterns in Harrisburg, 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 Harrisburg, January typically receives around 100 mm (3.9 inches) of precipitation spread over approximately 9 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 Harrisburg

In Harrisburg in January humidity is 84%. With an average temperature of 5°C (41°F), this humidity feels like a damp chill that seeps into your bones, making traveling uncomfortable as you navigate through the cold, heavy air that clings to your skin.

January Average Humidity in Harrisburg

This chart illustrates the average monthly humidity levels in Harrisburg, 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 Harrisburg is approximately 84%, 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 Harrisburg

In Harrisburg 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 Harrisburg, you can check the information here.

Maximum UV Index Levels in Harrisburg for January

The chart shows the monthly maximum UV Index (UVI) for Harrisburg 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 Harrisburg typically reaches 3, which falls under the moderate exposure category.

Data source: Harrisburg 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 Harrisburg Compares to Other Months

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

This table compares monthly weather conditions in Harrisburg, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	5°C (41°F)	100 mm (3.9 inches)	84%	moderate
February Weather	7°C (45°F)	172 mm (6.8 inches)	83%	high
March Weather	12°C (54°F)	166 mm (6.5 inches)	81%	very high
April Weather	16°C (61°F)	136 mm (5.4 inches)	81%	very high
May Weather	22°C (72°F)	146 mm (5.8 inches)	83%	extreme
June Weather	26°C (79°F)	114 mm (4.5 inches)	83%	extreme
July Weather	28°C (82°F)	112 mm (4.4 inches)	81%	extreme
August Weather	26°C (80°F)	108 mm (4.3 inches)	74%	very high
September Weather	24°C (76°F)	86 mm (3.4 inches)	71%	very high
October Weather	18°C (64°F)	129 mm (5.1 inches)	76%	high
November Weather	10°C (50°F)	78 mm (3.1 inches)	84%	moderate
December Weather	8°C (46°F)	134 mm (5.3 inches)	88%	moderate