September Weather in Trenton, United States

Last updated: June 24, 2025

In September, the average temperature in Trenton, United States hovers around 16°C (61°F). You can expect a minimum of 5°C (42°F) and a maximum of 27°C (81°F) during this time. Precipitation averages 95 mm (3.7 in) spread over about 7 days, contributing to a high average humidity of 77%. Prepare for a mix of mild weather and occasional rain!

September Temperature in Trenton

In September in Trenton, the average temperature is 16°C (61°F). The maximum can reach 27°C (81°F), while the minimum can drop as low as 5°C (42°F). This makes for a pleasantly mild climate, ideal for exploring the sights and enjoying outdoor activities.

September Weather in Trenton: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Trenton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Trenton, September typically has an average temperature of 16°C (61°F), with highs reaching up to 27°C (81°F) and lows dropping to around 5°C (42°F).

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

September Precipitation in Trenton

In Trenton in September, the precipitation amount is 95 mm (3.7 in) over the course of 7 days.

September Precipitation Trends in Trenton

The chart displays monthly precipitation patterns in Trenton, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Trenton, September typically receives around 95 mm (3.7 inches) of precipitation spread over approximately 7 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Trenton

In Trenton in September humidity is 77%. With an average temperature of 16°C (61°F), this humidity feels like a slight heaviness in the air, making every step feel a touch more effortful while traveling. The dampness clings to your skin, adding a layer of discomfort, yet the mild temperature invites you to explore the surroundings, blending the challenge of the humidity with an opportunity for a refreshing adventure.

September Average Humidity in Trenton

This chart illustrates the average monthly humidity levels in Trenton, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Trenton is approximately 77%, offering insight into how humid the weather typically is during this month.

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

September UV Index in Trenton

In Trenton in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Trenton.

Maximum UV Index Levels in Trenton for September

The chart shows the monthly maximum UV Index (UVI) for Trenton in September, 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 September, the maximum UV index in Trenton typically reaches 7, which falls under the high exposure category.

Data source: Trenton September 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 September Weather in Trenton Compares to Other Months

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

This table compares monthly weather conditions in Trenton, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	98 mm (3.9 inches)	88%	low
February Weather	-3°C (26°F)	90 mm (3.6 inches)	88%	moderate
March Weather	0°C (32°F)	73 mm (2.9 inches)	85%	moderate
April Weather	6°C (43°F)	129 mm (5.1 inches)	81%	high
May Weather	11°C (52°F)	92 mm (3.6 inches)	76%	very high
June Weather	16°C (61°F)	79 mm (3.1 inches)	74%	very high
July Weather	19°C (67°F)	80 mm (3.2 inches)	74%	very high
August Weather	20°C (68°F)	73 mm (2.9 inches)	74%	very high
September Weather	16°C (61°F)	95 mm (3.7 inches)	77%	high
October Weather	11°C (52°F)	107 mm (4.2 inches)	82%	moderate
November Weather	4°C (40°F)	130 mm (5.1 inches)	85%	moderate
December Weather	-1°C (30°F)	138 mm (5.4 inches)	84%	low