nomadseason

September Weather in South Lyon, United States

Last updated: June 24, 2025

In September, the average temperature in South Lyon, United States is a pleasant 18°C (65°F). However, you can expect a range of temperatures, with a minimum of 2°C (36°F) and a maximum of 33°C (92°F). Rainfall is moderate, totaling 73 mm (2.9 in) over about 10 days, while the average humidity sits at a comfortable 80%. Enjoy the diverse weather this month brings!

September Temperature in South Lyon

In September, in South Lyon, the average temperature is 18°C (65°F). The maximum can reach 33°C (92°F), while the minimum can be as low as 2°C (36°F). This temperature range makes South Lyon an ideal destination for travelers seeking both warm days and cool nights.

September Weather in South Lyon: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in South Lyon, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In South Lyon, September typically has an average temperature of 18°C (65°F), with highs reaching up to 33°C (92°F) and lows dropping to around 2°C (36°F).
JanFebMarAprMayJunJulAugSepOctNovDec262737465969747265533932
Data source: Temperature data for South Lyon generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in South Lyon

In South Lyon in September, the precipitation amount is 73 mm (2.9 in) over the course of 10 days.

September Precipitation Trends in South Lyon

The chart displays monthly precipitation patterns in South Lyon, 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 South Lyon, September typically receives around 73 mm (2.9 inches) of precipitation spread over approximately 10 days.
JanFebMarAprMayJunJulAugSepOctNovDec64667290111989074731047454
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in South Lyon

In South Lyon in September, humidity is 80%. With an average temperature of 18°C (65°F), this humidity feels like wandering through a warm, damp blanket, making every step slightly heavy and resulting in a constant sheen of sweat, which can be both refreshing and exhausting for travelers.

September Average Humidity in South Lyon

This chart illustrates the average monthly humidity levels in South Lyon, 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 South Lyon is approximately 80%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec88%87%85%86%80%80%80%81%80%84%90%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in South Lyon

In South Lyon 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 South Lyon.

Maximum UV Index Levels in South Lyon for September

The chart shows the monthly maximum UV Index (UVI) for South Lyon 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 South Lyon typically reaches 7, which falls under the high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec24599101097542
Data source: South Lyon 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 South Lyon Compares to Other Months

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

This table compares monthly weather conditions in South Lyon, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-3°C (26°F)63 mm (2.5 inches)88%low
February Weather-3°C (28°F)66 mm (2.6 inches)87%moderate
March Weather3°C (37°F)72 mm (2.8 inches)85%moderate
April Weather8°C (47°F)90 mm (3.6 inches)86%very high
May Weather15°C (60°F)111 mm (4.4 inches)80%very high
June Weather21°C (70°F)98 mm (3.9 inches)80%very high
July Weather23°C (74°F)90 mm (3.5 inches)80%very high
August Weather22°C (72°F)74 mm (2.9 inches)80%very high
September Weather18°C (65°F)73 mm (2.9 inches)80%high
October Weather12°C (54°F)104 mm (4.1 inches)84%moderate
November Weather4°C (39°F)74 mm (2.9 inches)89%moderate
December Weather0°C (32°F)54 mm (2.1 inches)86%low

Compare South Lyon's Climate with Cities Worldwide