September Weather in Thornhill, South Africa

Last updated: August 31, 2025

The average temperature in Thornhill, South Africa during September is a pleasant 16°C (61°F), with the potential to range from a cool 8°C (47°F) to a warm 34°C (93°F). Expect about 42 mm (1.6 in) of precipitation spread over 7 days, and prepare for high humidity levels at 75%.

September Temperature in Thornhill

In September in Thornhill, the average temperature is 16°C (61°F), with maximums reaching 34°C (93°F) and minimums dropping as low as 8°C (47°F). This weather makes Thornhill an ideal destination for travelers looking to enjoy a pleasant climate during their visit.

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

The chart illustrates September temperature patterns in Thornhill, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Thornhill, September typically has an average temperature of 16°C (61°F), with highs reaching up to 34°C (93°F) and lows dropping to around 8°C (47°F).

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

September Precipitation in Thornhill

In Thornhill in September, the total precipitation amount is 42 mm (1.6 in) accumulated over a span of 7 days.

September Precipitation Trends in Thornhill

The chart displays monthly precipitation patterns in Thornhill, 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 Thornhill, September typically receives around 42 mm (1.6 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 Thornhill

In Thornhill in September humidity is 75%. With an average temperature of 16°C (61°F), this humidity feels like a warm, muggy embrace, making traveling somewhat uncomfortable as you may find yourself constantly adjusting your clothing and seeking shade to escape the sticky air.

September Average Humidity in Thornhill

This chart illustrates the average monthly humidity levels in Thornhill, 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 Thornhill 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 Thornhill

In Thornhill 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 Thornhill.

Maximum UV Index Levels in Thornhill for September

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

Data source: Thornhill 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 Thornhill Compares to Other Months

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

This table compares monthly weather conditions in Thornhill, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	21°C (70°F)	28 mm (1.1 inches)	79%	extreme
February Weather	21°C (70°F)	48 mm (1.9 inches)	81%	extreme
March Weather	20°C (69°F)	43 mm (1.7 inches)	83%	extreme
April Weather	18°C (65°F)	28 mm (1.1 inches)	80%	very high
May Weather	17°C (63°F)	31 mm (1.2 inches)	76%	moderate
June Weather	16°C (62°F)	19 mm (0.7 inches)	72%	moderate
July Weather	16°C (60°F)	33 mm (1.3 inches)	74%	moderate
August Weather	15°C (59°F)	53 mm (2.1 inches)	72%	high
September Weather	16°C (61°F)	42 mm (1.6 inches)	75%	very high
October Weather	17°C (63°F)	38 mm (1.5 inches)	76%	extreme
November Weather	18°C (65°F)	47 mm (1.9 inches)	76%	extreme
December Weather	20°C (67°F)	48 mm (1.9 inches)	78%	extreme