September Weather in Guelph, Canada

Last updated: June 18, 2025

In Guelph, Canada, the average temperature in September hovers around 17°C (62°F), providing a comfortable climate for outdoor activities. However, be prepared for a wide range of temperatures, as it can dip to a chilly 1°C (34°F) or soar up to a warm 32°C (89°F). Rainfall is not uncommon, with an average of 71 mm (2.8 in) spread over 10 days, while the average humidity sits at a high 81%, adding to the overall atmosphere of this unique locale.

September Temperature in Guelph

In September in Guelph, the average temperature is 17°C (62°F). Maximum temperatures can reach 32°C (89°F), while minimums can dip as low as 1°C (34°F). Be sure to pack layers to stay comfortable while exploring the diverse climate!

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

The chart illustrates September temperature patterns in Guelph, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Guelph, September typically has an average temperature of 17°C (62°F), with highs reaching up to 32°C (89°F) and lows dropping to around 1°C (34°F).

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

September Precipitation in Guelph

In Guelph in September, the precipitation amount is 71 mm (2.8 in) over a duration of 10 days.

September Precipitation Trends in Guelph

The chart displays monthly precipitation patterns in Guelph, 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 Guelph, September typically receives around 71 mm (2.8 inches) of precipitation spread over approximately 10 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 Guelph

In Guelph in September, humidity is 81%. With an average temperature of 17°C (62°F), this humidity feels like a warm blanket enveloping you, making outdoor adventures feel sticky and requiring frequent breaks to stay comfortable while exploring.

September Average Humidity in Guelph

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

In Guelph in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Guelph.

Maximum UV Index Levels in Guelph for September

The chart shows the monthly maximum UV Index (UVI) for Guelph 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 Guelph typically reaches 7, which falls under the high exposure category.

Data source: Guelph 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 Guelph Compares to Other Months

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

This table compares monthly weather conditions in Guelph, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (23°F)	70 mm (2.8 inches)	90%	low
February Weather	-5°C (24°F)	75 mm (2.9 inches)	90%	moderate
March Weather	0°C (32°F)	65 mm (2.5 inches)	87%	moderate
April Weather	6°C (42°F)	103 mm (4.1 inches)	87%	very high
May Weather	13°C (56°F)	97 mm (3.8 inches)	82%	very high
June Weather	19°C (66°F)	105 mm (4.1 inches)	81%	very high
July Weather	22°C (71°F)	77 mm (3.0 inches)	79%	very high
August Weather	20°C (69°F)	95 mm (3.7 inches)	80%	very high
September Weather	17°C (62°F)	71 mm (2.8 inches)	81%	high
October Weather	10°C (50°F)	101 mm (4.0 inches)	84%	moderate
November Weather	2°C (36°F)	78 mm (3.1 inches)	88%	moderate
December Weather	-2°C (29°F)	72 mm (2.8 inches)	87%	low