nomadseason

September Weather in Rosny-sous-Bois, France

Last updated: August 23, 2025

In Rosny-sous-Bois, France, the average temperature for September hovers around 17°C (63°F), with a minimum dipping to 4°C (40°F) and a maximum soaring to 34°C (93°F). Expect around 51 mm (2.0 in) of precipitation over approximately 9 days and a comfortable average humidity of 76%.

September Temperature in Rosny-sous-Bois

In September, in Rosny-sous-Bois, the average temperature is 17°C (63°F), with maximums reaching 34°C (93°F) and minimums dropping to 4°C (40°F). This weather makes it a great time for travelers to enjoy outdoor activities while being prepared for varying temperatures.

September Weather in Rosny-sous-Bois: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Rosny-sous-Bois, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Rosny-sous-Bois, September typically has an average temperature of 17°C (63°F), with highs reaching up to 34°C (93°F) and lows dropping to around 4°C (40°F).
JanFebMarAprMayJunJulAugSepOctNovDec404347525866696862554643
Data source: Temperature data for Rosny-sous-Bois 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 Rosny-sous-Bois

In Rosny-sous-Bois in September, the total precipitation amount is 51 mm (2.0 in) spread over 9 days.

September Precipitation Trends in Rosny-sous-Bois

The chart displays monthly precipitation patterns in Rosny-sous-Bois, 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 Rosny-sous-Bois, September typically receives around 51 mm (2.0 inches) of precipitation spread over approximately 9 days.
JanFebMarAprMayJunJulAugSepOctNovDec6069733172685258518166106
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Rosny-sous-Bois

In Rosny-sous-Bois in September humidity is 76%. With an average temperature of 17°C (63°F), this humidity feels like traveling through a warm, enveloping blanket, making every outdoor adventure feel sticky and heavy, yet pleasantly refreshing when you find a cool breeze.

September Average Humidity in Rosny-sous-Bois

This chart illustrates the average monthly humidity levels in Rosny-sous-Bois, 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 Rosny-sous-Bois is approximately 76%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec91%89%85%84%82%80%73%68%76%88%92%93%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Rosny-sous-Bois

In Rosny-sous-Bois in September, the maximum UV index is 6, which corresponds to a high Exposure Category. The time to burn is approximately 25 minutes. To find the hourly UV index in Rosny-sous-Bois, you can refer to this Hourly UV Index in Rosny-sous-Bois.

Maximum UV Index Levels in Rosny-sous-Bois for September

The chart shows the monthly maximum UV Index (UVI) for Rosny-sous-Bois 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 Rosny-sous-Bois typically reaches 6, which falls under the high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec235689886421
Data source: Rosny-sous-Bois 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 Rosny-sous-Bois Compares to Other Months

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

This table compares monthly weather conditions in Rosny-sous-Bois, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather4°C (40°F)60 mm (2.3 inches)91%low
February Weather6°C (43°F)68 mm (2.7 inches)89%moderate
March Weather8°C (47°F)73 mm (2.9 inches)85%moderate
April Weather11°C (52°F)31 mm (1.2 inches)84%high
May Weather14°C (58°F)72 mm (2.8 inches)82%very high
June Weather19°C (66°F)68 mm (2.7 inches)80%very high
July Weather21°C (70°F)52 mm (2.0 inches)73%very high
August Weather20°C (68°F)58 mm (2.3 inches)68%very high
September Weather17°C (63°F)51 mm (2.0 inches)76%high
October Weather13°C (55°F)81 mm (3.2 inches)88%moderate
November Weather8°C (46°F)66 mm (2.6 inches)92%low
December Weather6°C (43°F)106 mm (4.2 inches)93%low

Compare Rosny-sous-Bois's Climate with Cities Worldwide