January Weather in Princeton, United States

Last updated: June 24, 2025

In January, the average temperature in Princeton, United States hovers around 7°C (45°F), creating a chill that underscores the beauty of the season. Expect a minimum plunge to -13°C (9°F) and a maximum rise to 26°C (79°F), showcasing the range of weather possibilities. With an average precipitation of 92 mm (3.6 in) over 8 days, be prepared for occasional showers. Additionally, the humidity level remains high at 85%, wrapping the landscape in a moist embrace.

January Temperature in Princeton

In January in Princeton, the average temperature is 7°C (45°F). Maximum temperatures can reach 26°C (79°F), while minimums can drop to as low as -13°C (9°F). Be prepared for a wide range of temperatures, making it ideal to pack layers for your travels.

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 7°C (45°F), with highs reaching up to 26°C (79°F) and lows dropping to around -13°C (9°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 precipitation amount is 92 mm (3.6 in), occurring over the course 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 92 mm (3.6 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 85%. With an average temperature of 7°C (45°F), this humidity feels like a damp chill that clings to your skin, making outdoor activities less enjoyable and requiring extra layers to stay comfortable while traveling.

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 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 Princeton

In Princeton in January, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Princeton for better planning.

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 4, 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	7°C (45°F)	92 mm (3.6 inches)	85%	moderate
February Weather	10°C (50°F)	92 mm (3.6 inches)	82%	high
March Weather	12°C (54°F)	73 mm (2.9 inches)	81%	very high
April Weather	17°C (63°F)	106 mm (4.2 inches)	80%	very high
May Weather	22°C (72°F)	118 mm (4.7 inches)	81%	very high
June Weather	25°C (77°F)	125 mm (4.9 inches)	81%	extreme
July Weather	27°C (81°F)	124 mm (4.9 inches)	81%	extreme
August Weather	26°C (79°F)	158 mm (6.2 inches)	80%	very high
September Weather	24°C (75°F)	134 mm (5.3 inches)	79%	very high
October Weather	19°C (66°F)	68 mm (2.7 inches)	80%	very high
November Weather	11°C (53°F)	84 mm (3.3 inches)	85%	moderate
December Weather	9°C (48°F)	109 mm (4.3 inches)	86%	moderate