January Weather in Princeton, United States

Last updated: June 24, 2025

In Princeton, United States, the average temperature in January hovers around 1°C (35°F), creating a chilly atmosphere perfect for bundling up. Be prepared for temperature fluctuations—with minimums dipping to a brisk -19°C (-2°F) and maximums reaching a mild 20°C (69°F). This month sees 95 mm (3.7 in) of precipitation spread over approximately 8 days, and with an average humidity of 84%, the air will feel quite damp. Make sure to dress appropriately and enjoy the seasonal charm!

January Temperature in Princeton

In January in Princeton, the average temperature is 1°C (35°F). The maximum can reach 20°C (69°F) and the minimum can be as low as -19°C (-2°F). It's advisable to pack both warm and lighter clothing for your travels, as the weather can vary dramatically during this time.

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 1°C (35°F), with highs reaching up to 20°C (69°F) and lows dropping to around -19°C (-2°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 95 mm (3.7 in) spread over 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 95 mm (3.7 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 84%. With an average temperature of 1°C (35°F), this humidity feels like a cold, damp chill that seeps into your bones, making it feel much colder than the thermometer suggests, which can be quite uncomfortable for 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 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 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	1°C (35°F)	95 mm (3.7 inches)	84%	moderate
February Weather	3°C (38°F)	119 mm (4.7 inches)	82%	moderate
March Weather	9°C (48°F)	146 mm (5.7 inches)	84%	high
April Weather	14°C (57°F)	118 mm (4.6 inches)	83%	very high
May Weather	20°C (69°F)	131 mm (5.2 inches)	80%	very high
June Weather	25°C (77°F)	124 mm (4.9 inches)	83%	extreme
July Weather	27°C (80°F)	73 mm (2.9 inches)	82%	very high
August Weather	25°C (78°F)	87 mm (3.4 inches)	82%	very high
September Weather	23°C (73°F)	77 mm (3.0 inches)	79%	very high
October Weather	16°C (61°F)	111 mm (4.4 inches)	79%	high
November Weather	7°C (45°F)	92 mm (3.6 inches)	88%	moderate
December Weather	5°C (41°F)	102 mm (4.0 inches)	87%	moderate