September Weather in Aylmer, Canada

Last updated: June 18, 2025

In September, the average temperature in Aylmer, Canada is a comfortable 18°C (65°F). Expect a range from a cool 5°C (42°F) to a warm 29°C (85°F). With 79 mm (3.1 in) of precipitation spread across about 10 days, the atmosphere is fairly humid, boasting an average humidity of 81%.

September Temperature in Aylmer

In September in Aylmer, the average temperature is 18°C (65°F). Maximums can reach 29°C (85°F), and minimums can be as low as 5°C (42°F). This makes Aylmer an ideal destination for travelers seeking mild weather and pleasant outdoor activities.

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

The chart illustrates September temperature patterns in Aylmer, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Aylmer, September typically has an average temperature of 18°C (65°F), with highs reaching up to 29°C (85°F) and lows dropping to around 5°C (42°F).

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

September Precipitation in Aylmer

In Aylmer in September, the precipitation amount is 79 mm (3.1 in) over a span of 10 days.

September Precipitation Trends in Aylmer

The chart displays monthly precipitation patterns in Aylmer, 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 Aylmer, September typically receives around 79 mm (3.1 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 Aylmer

In Aylmer in September, humidity is 81%. With an average temperature of 18°C (65°F), this humidity feels like a thick blanket wrapping around you, making every step feel heavier and the air thick and sultry—a challenging environment for traveling.

September Average Humidity in Aylmer

This chart illustrates the average monthly humidity levels in Aylmer, 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 Aylmer is approximately 81%, 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 Aylmer

In Aylmer 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 Aylmer.

Maximum UV Index Levels in Aylmer for September

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

Data source: Aylmer 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 Aylmer Compares to Other Months

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

This table compares monthly weather conditions in Aylmer, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-3°C (27°F)	77 mm (3.0 inches)	90%	moderate
February Weather	-3°C (27°F)	81 mm (3.2 inches)	90%	moderate
March Weather	1°C (34°F)	83 mm (3.3 inches)	87%	moderate
April Weather	6°C (43°F)	109 mm (4.3 inches)	87%	very high
May Weather	13°C (55°F)	101 mm (4.0 inches)	82%	very high
June Weather	19°C (66°F)	91 mm (3.6 inches)	81%	very high
July Weather	22°C (72°F)	91 mm (3.6 inches)	79%	very high
August Weather	22°C (71°F)	90 mm (3.6 inches)	80%	very high
September Weather	18°C (65°F)	79 mm (3.1 inches)	81%	very high
October Weather	12°C (55°F)	121 mm (4.8 inches)	84%	high
November Weather	5°C (41°F)	94 mm (3.7 inches)	88%	moderate
December Weather	1°C (33°F)	82 mm (3.2 inches)	87%	low