September Weather in Monona, United States

Last updated: June 24, 2025

In September, the average temperature in Monona, United States hovers around 18°C (65°F), with the minimum dipping to 1°C (35°F) and the maximum reaching a warm 33°C (91°F). Expect a precipitation amount of 121 mm (4.7 in) over approximately 11 days, accompanied by an average humidity of 74%. Prepare for a mix of weather as you enjoy your time in this beautiful location!

September Temperature in Monona

In September in Monona, the average temperature is 18°C (65°F). Maximums can reach 33°C (91°F), and minimums can drop as low as 1°C (35°F). This makes Monona a great destination for travelers looking for mild to warm weather, but it's essential to be prepared for a wide range of temperatures.

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

The chart illustrates September temperature patterns in Monona, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Monona, September typically has an average temperature of 18°C (65°F), with highs reaching up to 33°C (91°F) and lows dropping to around 1°C (35°F).

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

September Precipitation in Monona

In Monona in September, the total precipitation amount reaches 121 mm (4.7 in) over a span of 11 days.

September Precipitation Trends in Monona

The chart displays monthly precipitation patterns in Monona, 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 Monona, September typically receives around 121 mm (4.7 inches) of precipitation spread over approximately 11 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 Monona

In Monona in September humidity is 74%. With an average temperature of 18°C (65°F), this humidity feels like a warm, sticky embrace that can make even short walks feel laborious, leading travelers to seek shade and refreshment more often.

September Average Humidity in Monona

This chart illustrates the average monthly humidity levels in Monona, 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 Monona is approximately 74%, 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 Monona

In Monona 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 Monona.

Maximum UV Index Levels in Monona for September

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

Data source: Monona 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 Monona Compares to Other Months

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

This table compares monthly weather conditions in Monona, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-7°C (20°F)	41 mm (1.6 inches)	84%	moderate
February Weather	-6°C (21°F)	53 mm (2.1 inches)	85%	moderate
March Weather	2°C (36°F)	63 mm (2.5 inches)	84%	moderate
April Weather	8°C (46°F)	78 mm (3.1 inches)	83%	very high
May Weather	15°C (60°F)	154 mm (6.1 inches)	75%	very high
June Weather	22°C (71°F)	134 mm (5.3 inches)	79%	very high
July Weather	23°C (75°F)	113 mm (4.5 inches)	75%	very high
August Weather	21°C (71°F)	97 mm (3.8 inches)	69%	very high
September Weather	18°C (65°F)	121 mm (4.7 inches)	74%	very high
October Weather	10°C (50°F)	136 mm (5.4 inches)	79%	moderate
November Weather	2°C (36°F)	50 mm (2.0 inches)	88%	moderate
December Weather	-2°C (29°F)	39 mm (1.5 inches)	82%	low