September Weather in Duncan, Canada

Last updated: June 18, 2025

In Duncan, Canada, the average temperature in September hovers around 15°C (59°F). Expect a comfortable range, with minimum temperatures dipping to 5°C (42°F) and highs reaching up to 31°C (89°F). However, be prepared for some rain, as 120 mm (4.7 in) of precipitation can be expected over 11 days. With an average humidity of 76%, Duncan offers a refreshing yet humid climate during this month.

September Temperature in Duncan

In September in Duncan, the average temperature is 15°C (59°F). Maximums can reach 31°C (89°F), and minimums can be as low as 5°C (42°F). Be prepared for a wide range of temperatures, making it a great time for exploring with layered clothing.

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

The chart illustrates September temperature patterns in Duncan, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Duncan, September typically has an average temperature of 15°C (59°F), with highs reaching up to 31°C (89°F) and lows dropping to around 5°C (42°F).

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

September Precipitation in Duncan

In Duncan in September, the precipitation amount is 120 mm (4.7 in) during a span of 11 days.

September Precipitation Trends in Duncan

The chart displays monthly precipitation patterns in Duncan, 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 Duncan, September typically receives around 120 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 Duncan

In Duncan in September humidity is 76%. With an average temperature of 15°C (59°F), this humidity feels like a heavy blanket wrapping around you, making outdoor activities less enjoyable and often leading to a quick sense of fatigue while traveling.

September Average Humidity in Duncan

This chart illustrates the average monthly humidity levels in Duncan, 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 Duncan is approximately 76%, 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 Duncan

In Duncan 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 Duncan.

Maximum UV Index Levels in Duncan for September

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

Data source: Duncan 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 Duncan Compares to Other Months

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

This table compares monthly weather conditions in Duncan, 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 (38°F)	215 mm (8.5 inches)	86%	low
February Weather	2°C (36°F)	131 mm (5.2 inches)	85%	moderate
March Weather	5°C (41°F)	118 mm (4.6 inches)	86%	moderate
April Weather	8°C (47°F)	111 mm (4.4 inches)	86%	high
May Weather	12°C (55°F)	54 mm (2.1 inches)	81%	very high
June Weather	15°C (60°F)	48 mm (1.9 inches)	83%	very high
July Weather	18°C (65°F)	18 mm (0.7 inches)	84%	very high
August Weather	19°C (66°F)	24 mm (1.0 inches)	77%	very high
September Weather	15°C (59°F)	120 mm (4.7 inches)	76%	high
October Weather	9°C (49°F)	151 mm (6.0 inches)	88%	moderate
November Weather	6°C (43°F)	245 mm (9.6 inches)	87%	low
December Weather	3°C (37°F)	214 mm (8.4 inches)	87%	low