September Weather in Three Rivers, United States

Last updated: June 24, 2025

In Three Rivers, United States, the average temperature in September hovers around 28°C (83°F), with the potential to dip as low as 14°C (58°F) or soar up to 40°C (104°F). Visitors can expect about 92 mm (3.6 in) of precipitation over 11 days, along with an average humidity of 65%. Perfect for those who enjoy a warm, tropical climate!

September Temperature in Three Rivers

In September, in Three Rivers, the average temperature is 28°C (83°F). Maximums can reach up to 40°C (104°F), while minimums can drop as low as 14°C (58°F). Be prepared for warm days and cooler evenings when planning your travel.

September Weather in Three Rivers: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Three Rivers, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Three Rivers, September typically has an average temperature of 28°C (83°F), with highs reaching up to 40°C (104°F) and lows dropping to around 14°C (58°F).

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

September Precipitation in Three Rivers

In Three Rivers in September, the precipitation amount is 92 mm (3.6 in) spread over 11 days.

September Precipitation Trends in Three Rivers

The chart displays monthly precipitation patterns in Three Rivers, 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 Three Rivers, September typically receives around 92 mm (3.6 inches) of precipitation spread over approximately 11 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 Three Rivers

In Three Rivers in September, humidity is 65%. With an average temperature of 28°C (83°F), this humidity feels like a warm, tropical embrace that can make outdoor activities feel quite sticky and draining, so it's best to stay hydrated and take regular breaks in the shade.

September Average Humidity in Three Rivers

This chart illustrates the average monthly humidity levels in Three Rivers, 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 Three Rivers is approximately 65%, 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 Three Rivers

In Three Rivers in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Three Rivers.

Maximum UV Index Levels in Three Rivers for September

The chart shows the monthly maximum UV Index (UVI) for Three Rivers 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 Three Rivers typically reaches 11, which falls under the extreme exposure category.

Data source: Three Rivers 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 Three Rivers Compares to Other Months

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

This table compares monthly weather conditions in Three Rivers, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	14°C (57°F)	28 mm (1.1 inches)	79%	moderate
February Weather	15°C (60°F)	36 mm (1.4 inches)	79%	very high
March Weather	20°C (69°F)	46 mm (1.8 inches)	74%	very high
April Weather	23°C (74°F)	58 mm (2.3 inches)	76%	extreme
May Weather	27°C (81°F)	89 mm (3.5 inches)	81%	extreme
June Weather	29°C (85°F)	82 mm (3.2 inches)	76%	extreme
July Weather	30°C (87°F)	74 mm (2.9 inches)	66%	extreme
August Weather	31°C (88°F)	59 mm (2.3 inches)	58%	extreme
September Weather	28°C (83°F)	92 mm (3.6 inches)	65%	extreme
October Weather	24°C (76°F)	55 mm (2.2 inches)	74%	very high
November Weather	18°C (65°F)	40 mm (1.6 inches)	81%	high
December Weather	15°C (60°F)	41 mm (1.6 inches)	86%	moderate