September Weather in Geneva, United States

Last updated: June 24, 2025

In September, the average temperature in Geneva, United States hovers around 20°C (69°F). You can expect a minimum of 4°C (39°F) and a maximum of 33°C (91°F), creating a diverse climate. Prepare for 75 mm (2.9 in) of precipitation spread over approximately 8 days, and be ready for a moist atmosphere with an average humidity of 78%.

September Temperature in Geneva

In September in Geneva, the average temperature is 20°C (69°F). The maximum can reach 33°C (91°F), while the minimum can drop as low as 4°C (39°F). This variation in temperature makes Geneva a versatile destination for travelers seeking both warm days and cool evenings.

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

The chart illustrates September temperature patterns in Geneva, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Geneva, September typically has an average temperature of 20°C (69°F), with highs reaching up to 33°C (91°F) and lows dropping to around 4°C (39°F).

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

September Precipitation in Geneva

In Geneva in September, the precipitation amount is 75 mm (2.9 in) over a span of 8 days.

September Precipitation Trends in Geneva

The chart displays monthly precipitation patterns in Geneva, 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 Geneva, September typically receives around 75 mm (2.9 inches) of precipitation spread over approximately 8 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Geneva

In Geneva in September, humidity is 78%. With an average temperature of 20°C (69°F), this humidity feels like a warm, enveloping blanket, making travel somewhat uncomfortable as sweat clings to your skin and the air feels thick and heavy, urging you to seek out shaded areas and refreshing drinks.

September Average Humidity in Geneva

This chart illustrates the average monthly humidity levels in Geneva, 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 Geneva is approximately 78%, 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 Geneva

In Geneva 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 Geneva.

Maximum UV Index Levels in Geneva for September

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

Data source: Geneva 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 Geneva Compares to Other Months

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

This table compares monthly weather conditions in Geneva, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (29°F)	74 mm (2.9 inches)	85%	moderate
February Weather	0°C (32°F)	88 mm (3.4 inches)	85%	moderate
March Weather	5°C (42°F)	101 mm (4.0 inches)	86%	high
April Weather	10°C (51°F)	93 mm (3.7 inches)	87%	very high
May Weather	17°C (63°F)	127 mm (5.0 inches)	81%	very high
June Weather	22°C (73°F)	114 mm (4.5 inches)	82%	extreme
July Weather	24°C (76°F)	101 mm (4.0 inches)	81%	very high
August Weather	23°C (74°F)	102 mm (4.0 inches)	79%	very high
September Weather	20°C (69°F)	75 mm (2.9 inches)	78%	very high
October Weather	14°C (57°F)	97 mm (3.8 inches)	81%	high
November Weather	5°C (42°F)	82 mm (3.2 inches)	89%	moderate
December Weather	2°C (35°F)	67 mm (2.7 inches)	86%	low