nomadseason

September Weather in Dayton, United States

Last updated: June 24, 2025

In Dayton, United States, the average temperature in September is a pleasant 17°C (63°F). However, temperatures can vary significantly, with a minimum of 1°C (34°F) and a maximum reaching 36°C (96°F). This month also sees an average precipitation of 26 mm (1.0 in) spread over 4 days, resulting in an average humidity of 60%.

September Temperature in Dayton

In September in Dayton, the average temperature is 17°C (63°F), with maximums reaching up to 36°C (96°F) and minimums potentially dropping as low as 1°C (34°F). Be sure to pack layers for your trip, as the weather can vary significantly throughout the day.

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

The chart illustrates September temperature patterns in Dayton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Dayton, September typically has an average temperature of 17°C (63°F), with highs reaching up to 36°C (96°F) and lows dropping to around 1°C (34°F).
JanFebMarAprMayJunJulAugSepOctNovDec353441485765747262494134
Data source: Temperature data for Dayton 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 Dayton

In Dayton in September, the precipitation amount is 26 mm (1.0 in) over the course of 4 days.

September Precipitation Trends in Dayton

The chart displays monthly precipitation patterns in Dayton, 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 Dayton, September typically receives around 26 mm (1.0 inches) of precipitation spread over approximately 4 days.
JanFebMarAprMayJunJulAugSepOctNovDec671057158543041526577478
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Dayton

In Dayton in September humidity is 60%. With an average temperature of 17°C (63°F), this humidity feels like a slight weight in the air, making it perfect for leisurely strolls but a bit sticky for intense outdoor activities.

September Average Humidity in Dayton

This chart illustrates the average monthly humidity levels in Dayton, 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 Dayton is approximately 60%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%86%86%82%77%79%77%62%60%80%87%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Dayton

In Dayton 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 Dayton.

Maximum UV Index Levels in Dayton for September

The chart shows the monthly maximum UV Index (UVI) for Dayton 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 Dayton typically reaches 7, which falls under the high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec2467991097532
Data source: Dayton 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 Dayton Compares to Other Months

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

This table compares monthly weather conditions in Dayton, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather1°C (35°F)67 mm (2.7 inches)85%low
February Weather1°C (34°F)105 mm (4.1 inches)86%moderate
March Weather5°C (42°F)71 mm (2.8 inches)86%high
April Weather9°C (48°F)58 mm (2.3 inches)82%high
May Weather14°C (57°F)53 mm (2.1 inches)77%very high
June Weather18°C (65°F)30 mm (1.2 inches)79%very high
July Weather23°C (74°F)4 mm (0.1 inches)77%very high
August Weather22°C (73°F)15 mm (0.6 inches)62%very high
September Weather17°C (63°F)26 mm (1.0 inches)60%high
October Weather10°C (49°F)57 mm (2.3 inches)80%moderate
November Weather5°C (41°F)74 mm (2.9 inches)87%moderate
December Weather1°C (34°F)78 mm (3.1 inches)86%low

Compare Dayton's Climate with Cities Worldwide