September Weather in Canada, Mexico

Last updated: April 22, 2025

In September, Canada and Mexico experience a striking variation in weather conditions. With maximum temperatures soaring up to 36°C (97°F) and a comfortable average of 23°C (74°F), the warmth is notable, though it dips to a refreshing 15°C (59°F) at night. However, this warmth comes with considerable humidity, averaging 84%, and significant rainfall, as indicated by 164 mm (6.5 in) of precipitation over 22 days. This dynamic weather pattern creates a unique blend of summer’s heat and the rhythmic beauty of fall, inviting residents and travelers alike to explore the vibrant landscapes under varied skies.

September Temperature in Canada

As September rolls in, both Canada and Mexico experience a notable transition in temperatures, signaling the shift toward autumn. With a minimum of 15°C (59°F) and an average of 23°C (74°F), the month strikes a balance between summer warmth and the coolness of fall, reaching a maximum of 36°C (97°F). This gradual decline from the sizzling summer heat, seen in the preceding months, invites people to revel in comfortable outdoor activities while enjoying the vibrant autumn foliage. The steady average temperature of 23°C (74°F) reflects a harmonious blend of warm days and cooler evenings, making September a delightful time for exploration and outdoor gatherings across both nations.

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

The chart illustrates September temperature patterns in Canada, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec596367727575757573706460
Data source: Temperature data for Canada generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Canada

September marks a significant peak in precipitation across Canada and Mexico, delivering an impressive 164 mm (6.5 in) of rainfall over 22 days. This increase is particularly striking compared to the preceding months, as it follows a general upward trend starting in May. The transition from the drier summer months of July and August, with averages of 116 mm (4.6 in) and 95 mm (3.7 in) respectively, highlights the arrival of the fall season and its associated weather patterns. Notably, September outshines previous months in both total precipitation and the number of rainy days, underscoring a vital shift towards wetter conditions that prepare the landscape for the cooler autumn months ahead.

September Precipitation Trends in Canada

The chart displays monthly precipitation patterns in Canada, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3029484892148116951641453519
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Canada

As summer transitions into autumn, September in Canada and Mexico witnesses a notable rise in humidity, reaching 84%. This marks a slight increase from the drier months of July and August, which saw levels at 72% and 74% respectively. In fact, September's humidity reflects a broader trend, where the relative moisture begins to soar again, paving the way for the more humid tendencies of fall and winter. The months ahead, particularly October, will see humidity leap to 92%, drawing a stark contrast to the crisp air of midsummer. Overall, this month serves as a pivotal marker in the year’s climatic rhythm, bridging the gap between the heat of summer and the chill of winter.

September Average Humidity in Canada

This chart illustrates the average monthly humidity levels in Canada, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec89%86%83%80%82%79%72%74%84%92%91%91%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Canada

As September rolls around in Canada and Mexico, the UV Index remains a notable 13, placing it firmly in the extreme exposure category, with a burn time of just 10 minutes. This strong UV intensity mirrors the trend seen from April through August, where the Index consistently hovered between 13 and 14, indicating a prolonged period of high sun exposure risk. Despite slight fluctuations, the overall pattern shows that as summer gives way to fall, UV levels remain significant, reminding us of the importance of sun safety. Whether enjoying outdoor activities or basking in the late summer sun, staying informed about the Canada UV Index can help protect skin from harmful rays.

Maximum UV Index Levels in Canada for September

The chart shows the monthly maximum UV Index (UVI) for Canada 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.
JanFebMarAprMayJunJulAugSepOctNovDec810131413131413131197
Data source: Canada 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.

September Sunshine in Canada

As summer transitions to autumn, September in Canada and Mexico still basks in ample sunshine, with an impressive 289 hours of glorious sunlight gracing the month. This marks a slight dip from the sun-drenched heights of July and August, which captured the season's full essence with 327 and 325 hours respectively. However, September remains a shining gem compared to earlier months, like January with only 193 hours. The gradual decline in sunlight as winter approaches is evident, yet this month offers a warm farewell to summer, inviting outdoor adventures before the chill sets in. Overall, September strikes a delightful balance, combining warm, sunny days and the promise of beautiful fall foliage, making it a perfect time to bask in the outdoors.

Monthly Sunshine Duration in Canada: September Highlighted

The September sunshine duration represents the total number of hours Canada experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec193h237h279h283h314h317h327h325h289h275h247h261h
Data source: Canada September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Canada During September

As summer fades and September begins, Canada experiences a notable decline in sunshine, with only a 21% chance of sunny weather. This marks one of the year's lowest probabilities, reflecting a transition towards the more overcast months ahead. In contrast, Mexico remains a haven for sun-seekers, often enjoying bright, clear skies as it moves into the fall. While Canada bids farewell to warm, radiant days, Mexico's sunny disposition continues, highlighting a stark difference in weather patterns as the seasons shift. Ultimately, whether you're craving the crispness of autumn in Canada or the lingering warmth in Mexico, understanding these trends can help in planning your ideal September getaway.

Percentage of Sunny Days in September in Canada

The chart illustrates the percentage of sunny days in Canada throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Canada experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec39%58%54%45%40%20%26%40%21%45%51%66%
Data source: Canada September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Canada in September

As summer's warmth begins to wane, September in Canada and Mexico offers a gentle transition, featuring 12 hours of daylight. This month maintains the same daylight length as April and August, showcasing a balanced shift from the peak summer brightness. After peaking at 13 hours during the mid-year months, daylight duration declines gradually, hinting at the approaching autumn. The consistent daylight hours not only highlight the steady climatic rhythm but also suggest an ideal time for outdoor activities before the shorter days of fall set in. This smooth transition reflects the natural ebb and flow of daylight throughout the year, promoting appreciation for the changing seasons in both countries.

Average Daylight Hours in Canada for September

The chart illustrates the variation in daylight duration in Canada throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 57m11h 25m12h 1m12h 39m13h 11m13h 26m13h 17m12h 50m12h 13m11h 36m11h 4m10h 48m
Data source: Canada daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Canada

As summer transitions into fall, September brings a noticeable dip in average wind speed across both Canada and Mexico, settling at 1.8 m/s (4 mph), which is consistent with the gentle breezes of October and November. This slight decrease contrasts with the more invigorating winds experienced in the spring and early summer months, when speeds peaked at 2.6 m/s (6 mph) in April. It seems that as the vibrant warmth of summer fades, so too does the wind's vigor, embracing a calmer pace that marks the approaching chill of winter. Overall, this evolving trend showcases nature's rhythm, where brisk gusts give way to serene airs, inviting a moment of pause to appreciate the changing seasons.

Average September Wind Speed in Canada

The chart displays monthly wind speed patterns in Canada, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec1.92.12.52.62.52.02.12.51.8 m/s1.81.81.7
Data source: Canada September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Canada Compares to Other Months

The weather in Canada changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Canada and find detailed weather information for every month.

In September, the weather typically features warmer temperatures, with a minimum of 15°C (59°F) and an average high reaching up to 36°C (97°F). This month also brings significant rainfall, averaging 164 mm (6.5 in) over 22 days, and an elevated humidity level of 84%. In contrast, January presents a much cooler climate, with temperatures ranging from a low of 3°C (38°F) to a high of 33°C (92°F). Notably, January experiences far less precipitation, averaging only 30 mm (1.2 in) over just 6 days, although humidity remains high at 88%. This stark difference in weather patterns highlights the transition from the warmth and moisture of September to the cooler, drier conditions of January. For more details on January weather, check out Canada weather in January.

In September, the weather is considerably warmer, with average temperatures ranging from a minimum of 15°C (59°F) to a maximum of 36°C (97°F), making it a hot month overall. However, it is also quite wet, experiencing 164 mm (6.5 in) of precipitation over 22 days and a high humidity level of 84%. In contrast, February offers cooler temperatures, with a minimum of 3°C (37°F) and an average of 17°C (63°F), yet still can reach up to 35°C (95°F). The precipitation is significantly lower at 29 mm (1.2 in) over just 8 days, accompanied by a slightly higher humidity of 86%. For more details on February weather, you can visit Canada weather in February.

September and March present notably different weather conditions. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 36°C (97°F), with an average of 23°C (74°F). The month is marked by relatively high humidity at 84% and significant precipitation, totaling 164 mm (6.5 in) over 22 days. In contrast, March has cooler temperatures, with a minimum of 3°C (38°F) and an average of 19°C (67°F), peaking at 37°C (99°F). Precipitation is far less in March, at only 48 mm (1.9 in) over 10 days, and humidity remains slightly lower at 83%. For more detailed weather information, you can check Canada weather in March.

When comparing the weather in September and April, notable differences can be observed. September typically features a wider temperature range, with minimums around 15°C (59°F) and maximums reaching up to 36°C (97°F), averaging 23°C (74°F). Additionally, September experiences considerably higher precipitation, with 164 mm (6.5 in) spread over 22 days and humidity levels at 84%.

In contrast, April tends to have milder weather, with a minimum temperature of 10°C (50°F) and maximums soaring to 39°C (102°F), averaging 22°C (72°F). Precipitation during April is much lower at 48 mm (1.9 in) over just 9 days, accompanied by slightly lower humidity at 80%. For a more in-depth look, you can visit Canada weather in April.

In comparing September and May weather, September tends to be warmer overall, featuring a higher maximum temperature of 36°C (97°F) compared to May's peak of 38°C (101°F). The average temperatures are closely aligned, with September averaging 23°C (74°F) and May at 24°C (76°F). Rainfall is more pronounced in September, with 164 mm (6.5 in) spread over 22 days, while May experiences less precipitation at 92 mm (3.6 in) over 19 days. Both months exhibit high humidity levels, with September at 84% and May slightly lower at 82%. For more details on May's weather, you can visit Canada weather in May.

September and June exhibit similar temperature ranges, with both months experiencing maximums around 36°C (97°F to 98°F). However, September tends to be slightly cooler with an average temperature of 23°C (74°F) compared to June's 24°C (75°F). When it comes to precipitation, September is wetter, averaging 164 mm (6.5 in) over 22 days, whereas June sees 148 mm (5.8 in) over 23 days. Humidity levels are also higher in September at 84%, contrasting with June's 79%. This makes September feel more humid and damp despite the warm temperatures. For more detailed insights, check out Canada weather in June.

In comparing the weather of September and July, we see that September experiences slightly cooler average temperatures, ranging from a minimum of 15°C (59°F) to a maximum of 36°C (97°F), whereas July has higher temperatures, with a minimum of 17°C (62°F) and a maximum of 34°C (94°F). Additionally, September is significantly wetter, with 164 mm (6.5 in) of precipitation over 22 days, compared to July's 116 mm (4.6 in) over 19 days. Humidity levels also differ, as September has a higher humidity at 84%, while July sits at a more comfortable 72%. For a more detailed look into July weather patterns, you can visit Canada weather in July.

In comparing the weather between September and August, September tends to be slightly cooler, with average temperatures ranging from a minimum of 15°C (59°F) to a maximum of 36°C (97°F), compared to August's 17°C (62°F) minimum and 34°C (94°F) maximum. Additionally, September experiences significantly higher precipitation, totaling 164 mm (6.5 in) over 22 days, whereas August sees only 95 mm (3.7 in) across 18 days. The humidity levels also rise in September to 84%, compared to August's 74%, making September feel more humid and damp. For a more detailed overview, you can visit Canada weather in August.

September and October present a noticeable shift in weather patterns. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 36°C (97°F), with an average of 23°C (74°F). The month experiences considerable precipitation, totaling 164 mm (6.5 in) over 22 days, coupled with a high humidity level of 84%. In contrast, October sees cooler temperatures, with a minimum of 9°C (49°F) and a maximum of 32°C (90°F), averaging 21°C (70°F). Although the precipitation amount decreases slightly to 145 mm (5.7 in) over 15 days, the humidity rises to 92%. This transition marks the move from the warmer, wetter late summer to a cooler, more humid autumn. For more detailed information, visit Canada weather in October.

September and November present a stark contrast in weather conditions. September boasts warmer temperatures with a minimum of 15°C (59°F) and a maximum reaching 36°C (97°F), while averaging around 23°C (74°F). This month is also characterized by significant rainfall, totaling 164 mm (6.5 in) over 22 days, coupled with high humidity levels at 84%. In contrast, November experiences much cooler temperatures, with a minimum dropping to 1°C (33°F) and a more moderate maximum of 32°C (89°F), averaging 18°C (64°F). Precipitation is considerably less in November, totaling only 35 mm (1.4 in) over 9 days, and humidity remains high at 91%. For a deeper look into November's weather patterns, check out Canada weather in November.

In September, the weather is characterized by warmer temperatures, with a minimum of 15°C (59°F) and a maximum reaching up to 36°C (97°F). The month experiences substantial precipitation, totaling 164 mm (6.5 in) over 22 days, and humidity levels remain high at 84%.

In contrast, December brings a significant drop in temperatures, starting from a minimum of 1°C (35°F) and averaging around 16°C (60°F), with a maximum of 31°C (88°F). The month is much drier, with only 19 mm (0.8 in) of rain over just 4 days, although humidity rises slightly to 91%.

For more detailed information, you can visit Canada weather in December.

Compare Canada's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Canada

As summer gracefully transitions into fall, September in Canada showcases a dynamic blend of weather characteristics that set it apart from other months. Temperatures can soar to a sweltering 36°C, yet the average settles at a comfortable 23°C while cooler evenings remind us of the approaching autumn chill. Rain is more frequent during this month, with precipitation occurring on nearly three-quarters of the days, leading to an overall humidity level of 84% that envelops the landscape. This unique combination of warmth and moisture creates a vibrant atmosphere, making September a transformative time for nature and a striking contrast to the typically drier and cooler months to come. For a deeper understanding of Canada’s climate variations, explore Canada Climate.