September Weather in Calmar, United States

Last updated: June 24, 2025

In Calmar, United States, the average temperature in September is a pleasant 18°C (65°F). However, be prepared for some variability, with temperatures dipping as low as 2°C (35°F) and soaring to a maximum of 32°C (90°F). During this month, expect 123 mm (4.8 in) of precipitation over approximately 10 days, contributing to an average humidity level of 74%.

September Temperature in Calmar

In September in Calmar, the average temperature is 18°C (65°F). Maximums can reach 32°C (90°F) and minimums can be as low as 2°C (35°F). This diverse temperature range makes it essential for travelers to pack for both warm and cool conditions.

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

The chart illustrates September temperature patterns in Calmar, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Calmar, September typically has an average temperature of 18°C (65°F), with highs reaching up to 32°C (90°F) and lows dropping to around 2°C (35°F).

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

September Precipitation in Calmar

In Calmar in September, the total precipitation amount is 123 mm (4.8 in) over the course of 10 days.

September Precipitation Trends in Calmar

The chart displays monthly precipitation patterns in Calmar, 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 Calmar, September typically receives around 123 mm (4.8 inches) of precipitation spread over approximately 10 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Calmar

In Calmar 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 Calmar

This chart illustrates the average monthly humidity levels in Calmar, 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 Calmar 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 Calmar

In Calmar 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 Calmar.

Maximum UV Index Levels in Calmar for September

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

Data source: Calmar 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 Calmar Compares to Other Months

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

This table compares monthly weather conditions in Calmar, 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)	39 mm (1.5 inches)	84%	moderate
February Weather	-7°C (20°F)	52 mm (2.0 inches)	85%	moderate
March Weather	2°C (35°F)	64 mm (2.5 inches)	84%	moderate
April Weather	7°C (45°F)	80 mm (3.2 inches)	83%	very high
May Weather	15°C (59°F)	155 mm (6.1 inches)	75%	very high
June Weather	22°C (71°F)	130 mm (5.1 inches)	79%	very high
July Weather	23°C (74°F)	106 mm (4.2 inches)	75%	very high
August Weather	21°C (70°F)	109 mm (4.3 inches)	69%	very high
September Weather	18°C (65°F)	123 mm (4.8 inches)	74%	very high
October Weather	10°C (50°F)	133 mm (5.2 inches)	79%	moderate
November Weather	2°C (35°F)	53 mm (2.1 inches)	88%	moderate
December Weather	-3°C (28°F)	38 mm (1.5 inches)	82%	low