September Weather in Fort Mill, United States

Last updated: June 24, 2025

In September, the average temperature in Fort Mill, United States is a pleasant 24°C (75°F). Temperatures can vary significantly, with minimums dipping to 8°C (47°F) and maximums soaring to 35°C (95°F). Expect 128 mm (5.0 in) of precipitation spread over approximately 8 days, and a comfortable average humidity of 75%. Whether you’re exploring the outdoors or enjoying indoor activities, there’s plenty to experience this month!

September Temperature in Fort Mill

In September in Fort Mill, the average temperature is 24°C (75°F). Maximum temperatures can reach 35°C (95°F), while minimums can drop as low as 8°C (47°F). Be prepared for a range of weather conditions and enjoy a comfortable stay!

September Weather in Fort Mill: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Fort Mill, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Fort Mill, September typically has an average temperature of 24°C (75°F), with highs reaching up to 35°C (95°F) and lows dropping to around 8°C (47°F).

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

September Precipitation in Fort Mill

In Fort Mill in September, the precipitation amount is 128 mm (5.0 in) over a period of 8 days.

September Precipitation Trends in Fort Mill

The chart displays monthly precipitation patterns in Fort Mill, 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 Fort Mill, September typically receives around 128 mm (5.0 inches) of precipitation spread over approximately 8 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 Fort Mill

In Fort Mill in September humidity is 75%. With average temperature 24°C (75°F), this humidity feels like a thick blanket wrapping around you, making outdoor activities feel especially stifling and leaving you yearning for cool breezes and refreshingly cold drinks.

September Average Humidity in Fort Mill

This chart illustrates the average monthly humidity levels in Fort Mill, 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 Fort Mill is approximately 75%, 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 Fort Mill

In Fort Mill in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Fort Mill.

Maximum UV Index Levels in Fort Mill for September

The chart shows the monthly maximum UV Index (UVI) for Fort Mill 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 Fort Mill typically reaches 9, which falls under the very high exposure category.

Data source: Fort Mill 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 Fort Mill Compares to Other Months

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

This table compares monthly weather conditions in Fort Mill, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	7°C (45°F)	93 mm (3.7 inches)	86%	moderate
February Weather	10°C (50°F)	120 mm (4.7 inches)	85%	high
March Weather	12°C (55°F)	89 mm (3.5 inches)	84%	very high
April Weather	17°C (63°F)	104 mm (4.1 inches)	82%	very high
May Weather	22°C (72°F)	106 mm (4.2 inches)	83%	very high
June Weather	25°C (77°F)	79 mm (3.1 inches)	82%	extreme
July Weather	27°C (81°F)	101 mm (4.0 inches)	80%	extreme
August Weather	26°C (79°F)	114 mm (4.5 inches)	74%	very high
September Weather	24°C (75°F)	128 mm (5.0 inches)	75%	very high
October Weather	19°C (66°F)	87 mm (3.4 inches)	79%	very high
November Weather	11°C (52°F)	90 mm (3.5 inches)	87%	moderate
December Weather	9°C (48°F)	124 mm (4.9 inches)	87%	moderate