September Weather in Trumbull, United States

Last updated: June 24, 2025

The average temperature in Trumbull, United States during September is a pleasant 20°C (68°F). Temperatures can range from a cool 8°C (47°F) to a warm 33°C (91°F), making it a month of diverse weather. Expect about 105 mm (4.1 in) of precipitation spread over 10 days, contributing to an average humidity of 68%. Whether you're looking to enjoy sunny days or embrace cooler evenings, Trumbull offers a dynamic climate this month!

September Temperature in Trumbull

In September in Trumbull, the average temperature is 20°C (68°F). Maximums can reach 33°C (91°F), while minimums can drop as low as 8°C (47°F). This mild climate makes Trumbull an ideal destination for travelers seeking comfortable weather and the opportunity to explore the outdoors.

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

The chart illustrates September temperature patterns in Trumbull, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Trumbull, September typically has an average temperature of 20°C (68°F), with highs reaching up to 33°C (91°F) and lows dropping to around 8°C (47°F).

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

September Precipitation in Trumbull

In Trumbull in September, the precipitation amount is 105 mm (4.1 in) over the course of 10 days.

September Precipitation Trends in Trumbull

The chart displays monthly precipitation patterns in Trumbull, 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 Trumbull, September typically receives around 105 mm (4.1 inches) of precipitation spread over approximately 10 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Trumbull

In Trumbull in September humidity is 68%. With an average temperature of 20°C (68°F), this humidity feels like a warm embrace, making it ideal for leisurely strolls while also prompting travelers to stay hydrated and seek out refreshing breaks from the heat.

September Average Humidity in Trumbull

This chart illustrates the average monthly humidity levels in Trumbull, 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 Trumbull is approximately 68%, 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 Trumbull

In Trumbull in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Trumbull.

Maximum UV Index Levels in Trumbull for September

The chart shows the monthly maximum UV Index (UVI) for Trumbull 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 Trumbull typically reaches 8, which falls under the very high exposure category.

Data source: Trumbull 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 Trumbull Compares to Other Months

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

This table compares monthly weather conditions in Trumbull, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	0°C (33°F)	77 mm (3.0 inches)	84%	moderate
February Weather	1°C (35°F)	114 mm (4.5 inches)	82%	moderate
March Weather	4°C (40°F)	99 mm (3.9 inches)	81%	high
April Weather	9°C (49°F)	135 mm (5.3 inches)	78%	very high
May Weather	15°C (59°F)	119 mm (4.7 inches)	69%	very high
June Weather	20°C (69°F)	95 mm (3.7 inches)	69%	very high
July Weather	24°C (76°F)	132 mm (5.2 inches)	62%	very high
August Weather	23°C (74°F)	102 mm (4.0 inches)	65%	very high
September Weather	20°C (68°F)	105 mm (4.1 inches)	68%	very high
October Weather	15°C (59°F)	152 mm (6.0 inches)	74%	high
November Weather	7°C (46°F)	100 mm (4.0 inches)	82%	moderate
December Weather	3°C (37°F)	135 mm (5.3 inches)	80%	low