January Weather in Princeton, United States

Last updated: June 24, 2025

In January, the average temperature in Princeton, United States hovers around 3°C (38°F). Despite the chill, temperatures can swing widely with a minimum of -16°C (4°F) and a maximum reaching 20°C (68°F). Be prepared for some wet days, as 98 mm (3.8 in) of precipitation may fall over 8 days, and expect the air to feel quite humid, with an average humidity of 86%.

January Temperature in Princeton

In January, in Princeton, the average temperature is 3°C (38°F). Maximum temperatures can reach 20°C (68°F), while minimums can dip as low as -16°C (4°F). Be prepared for a wide range of temperatures when traveling during this month!

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

The chart illustrates January temperature patterns in Princeton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Princeton, January typically has an average temperature of 3°C (38°F), with highs reaching up to 20°C (68°F) and lows dropping to around -16°C (4°F).

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

January Precipitation in Princeton

In Princeton in January, the total precipitation amount is 97 mm (3.8 in), occurring over a span of 8 days.

January Precipitation Trends in Princeton

The chart displays monthly precipitation patterns in Princeton, 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 Princeton, January typically receives around 97 mm (3.8 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 Princeton

In Princeton in January humidity is 86%. With an average temperature of 3°C (38°F), this humidity feels like a damp chill that seeps through your layers, making traveling uncomfortable as breath clouds visibly in the crisp air.

January Average Humidity in Princeton

This chart illustrates the average monthly humidity levels in Princeton, 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 Princeton is approximately 86%, 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 Princeton

In Princeton 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 Princeton, you can check the information here.

Maximum UV Index Levels in Princeton for January

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

Data source: Princeton 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 Princeton Compares to Other Months

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

This table compares monthly weather conditions in Princeton, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	3°C (38°F)	97 mm (3.8 inches)	86%	moderate
February Weather	5°C (42°F)	150 mm (5.9 inches)	84%	high
March Weather	10°C (51°F)	135 mm (5.3 inches)	84%	high
April Weather	14°C (58°F)	138 mm (5.4 inches)	80%	very high
May Weather	21°C (69°F)	118 mm (4.7 inches)	82%	extreme
June Weather	25°C (77°F)	118 mm (4.6 inches)	83%	extreme
July Weather	27°C (81°F)	106 mm (4.2 inches)	79%	very high
August Weather	26°C (78°F)	104 mm (4.1 inches)	76%	very high
September Weather	23°C (74°F)	93 mm (3.7 inches)	75%	very high
October Weather	17°C (63°F)	108 mm (4.3 inches)	74%	high
November Weather	9°C (48°F)	96 mm (3.8 inches)	85%	moderate
December Weather	6°C (44°F)	119 mm (4.7 inches)	88%	moderate