Last updated: April 22, 2025
As September unfolds in Yellowknife, Canada, temperatures begin to cool, with the maximum reaching a pleasant 22°C (71°F), while the average settles around 8°C (47°F). Nights can be crisp, dipping to a minimum of -4°C (25°F), signaling the approach of autumn. This month sees an average precipitation of 28 mm (1.1 in) over six days, contributing to an humidity level of 86% that envelops the city in a refreshing, albeit damp, atmosphere. Whether you’re exploring the natural beauty or enjoying the changing leaves, September in Yellowknife offers a dynamic blend of summer warmth and the crispness of fall.
As September arrives in Yellowknife, Canada, temperatures begin to showcase a notable shift from the summer warmth to the crispness of autumn. With a minimum of -4°C (25°F) and a maximum peaking at 22°C (71°F), the average temperature settles around a comfortable 8°C (47°F). This transitional month marks a significant cool-down after the warmth of August, which frequently enjoys highs of 32°C (90°F). As the days shorten and the air grows brisk, the vibrant hues of fall foliage start to emerge, inviting both locals and visitors to revel in the beauty of the changing season. The noticeable drop signals the approach of winter, making September a unique blend of lingering summer vibes and the crisp, invigorating air of autumn.
September marks a notable transition in Yellowknife's precipitation patterns, blending the remnants of summer with the onset of autumn. With 28 mm (1.1 in) of rain spread over approximately 6 days, the month experiences a moderate decrease compared to the wetter months of July and August, which boast over 55 mm (2.2 in) each. This reduction in rainfall signals the gradual shift towards the colder months ahead. Interestingly, while September's precipitation is less than summer's peak, it remains significantly higher than the drier winter months, hinting at a brisk but temperate transition. As the days grow shorter and temperatures begin to cool, residents can expect September's rain to nourish the landscape, preparing it for the frosty embrace of winter.
September brings a noticeable shift in humidity levels in Yellowknife, Canada, as it settles at 86%. This marks a return to the more humid conditions experienced earlier in the year, following a drier stretch during the summer months when humidity dipped to its lowest at 69% in June. While the summer's warmth often correlates with lower humidity, September's percentage indicates a transitional phase, bridging summer and winter. As the days grow shorter and cooler, the increase in moisture in the air hints at the approaching winter months, where humidity levels will rise dramatically, peaking at an impressive 100% by December. This gradual annual cycle underscores how Yellowknife's climate continually fluctuates, reflecting its unique Northern geography.
As September arrives in Yellowknife, Canada, the UV Index shows a slight decline to 4, indicating a moderate exposure category, with a burn time of approximately 30 minutes under direct sunlight. This month marks a transition from the high levels of July and August, where the Index peaked at 6, and reminds residents that while the days are getting shorter and cooler, sun protection is still essential. As autumn sets in, the UV Index will continue to drop, leading into the lower levels found in the following months. Understanding these trends is crucial for anyone enjoying outdoor activities during the change of seasons. For more detailed insights, check the Yellowknife UV Index.
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In September, Yellowknife basks in the glow of 209 hours of sunshine, marking a gentle transition as autumn emerges. This month continues the trend set by the summer months, showcasing a nostalgic charm as daylight begins to wane. Following the sun-soaked days of July and August, which saw peak hours of 378 and 301, respectively, September allows residents and visitors to savor the lingering warmth of late summer. However, as the days shorten and the sun begins its retreat, the hours of sunlight drop significantly from the long summer days, subtly hinting at the colder months ahead. This gradual decrease in daylight serves as a vibrant reminder of the cyclical rhythms of life in this northern territory, where each season paints its own remarkable portrait.
In Yellowknife, Canada, the likelihood of sunny weather experiences a noticeable decline as summer gives way to autumn. While May basks in a promising 45% chance of sunshine, this figure gradually diminishes through the warm months of June (43%) and July (41%), before taking a dip to a mere 20% in September. This trend illustrates how the vibrant summer fades, casting a shadow over the chances of clear skies, eventually settling at the same low levels of 20% seen in November. As the days grow shorter, residents and visitors may want to savor those fleeting sun-filled moments before the long, dark winter descends.
As September unfolds in Yellowknife, Canada, the daylight hours begin their gradual descent from the heights of summer. With 12 hours of daylight, the month marks a stark contrast to the sunlit bliss of June, which boasted nearly 19 hours. This transition serves as a reminder of the shifting seasons, as the vibrant hues of autumn paint the landscape, and the days start to noticeably shorten. Following the warmth of summer, September's daylight invites residents to relish in the crisp air and golden leaves, heralding the approach of the darker months ahead. As daylight dwindles into October, dropping to 9 hours, it's clear that nature is preparing for the long, dark winter ahead, even as September offers a final glimpse of summer’s lingering glow.
September in Yellowknife brings a refreshing breeze, with an average wind speed of 3.7 m/s (8 mph), tying with the winds earlier in the year for a consistent feel. This pleasant yet brisk wind complements the changing colors of autumn, as summer fades into fall. Throughout the year, the wind speeds show a gradual increase from the more sheltered months of winter, peaking slightly in October at 4.1 m/s (9 mph). This trend highlights a subtle shift towards stronger breezes as seasons transition, making September a delightful precursor to the more robust winds of autumn. With such consistent breezes, Yellowknife invites residents and visitors alike to enjoy the crisp air and the stunning natural landscape as it transforms with the arrival of fall.
The weather in Yellowknife 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 Yellowknife and find detailed weather information for every month.
September and January present drastically different weather conditions. In September, temperatures range from a chilly min of -4°C (25°F) to a comfortable max of 22°C (71°F), with an average of 8°C (47°F) and about 28 mm of precipitation over 6 days. The humidity is relatively high at 86%, creating a crisp autumnal feel. In contrast, January is significantly colder, featuring a harsh min of -44°C (-47°F) and an average of -24°C (-11°F), with a max of only -7°C (20°F). Precipitation drops to 16 mm over just 4 days, and the humidity rises to a staggering 98%, contributing to the frigid winter atmosphere. For a detailed overview of the weather in January, visit Yellowknife weather in January.
In comparing the weather between September and February, the contrast is striking. September experiences milder temperatures, with a minimum of -4°C (25°F), an average of 8°C (47°F), and a maximum reaching 22°C (71°F). This month also sees a fair amount of precipitation, totaling 28 mm (1.1 in) over approximately six days and exhibiting relatively high humidity at 86%.
In stark contrast, February is characterized by extreme cold, featuring a minimum temperature of -48°C (-54°F), an average of -25°C (-13°F), and a maximum of just -1°C (30°F). Precipitation is significantly lower in February, at only 11 mm (0.4 in) over two days, along with an even higher humidity level of 97%. For more details on February weather, visit Yellowknife weather in February.
September and March present starkly contrasting weather conditions. In September, temperatures range from a chilly minimum of -4°C (25°F) to a pleasant maximum of 22°C (71°F), with an average of 8°C (47°F) and a humidity level of 86%. The month experiences about 28 mm (1.1 in) of precipitation over six days. In contrast, March is significantly colder, with temperatures dipping to as low as -43°C (-46°F) and averaging -17°C (2°F), only reaching a maximum of 7°C (44°F). Precipitation is slightly lower at 18 mm (0.7 in) over five days, and humidity is notably high at 94%. For a more detailed look at March weather, you can visit Yellowknife weather in March.
September and April present stark contrasts in weather conditions. In September, temperatures range from a low of -4°C (25°F) to a pleasant maximum of 22°C (71°F), with an average of 8°C (47°F). The month experiences about 28 mm (1.1 in) of precipitation over approximately 6 days, coupled with a relatively high humidity of 86%. Conversely, April is much colder, featuring temperatures that dip as low as -31°C (-24°F) and a maximum of only 13°C (55°F), with an average of -7°C (19°F). Precipitation is lighter in April, totaling 16 mm (0.6 in) over 4 days, yet humidity remains consistent at 86%. For more detailed information, you can check Yellowknife weather in April.
When comparing the weather between September and May, September offers a broader temperature range, with minimums around -4°C (25°F) and maximums reaching 22°C (71°F). The humidity also tends to be higher in September at 86%, contributing to a more overcast feel with approximately 28 mm of precipitation over six days. In contrast, May experiences colder minimum temperatures of -22°C (-8°F) and an average of 5°C (41°F), with maximums peaking at 26°C (79°F). The month sees less precipitation, about 20 mm, but it falls over only four days and comes with lower humidity levels of 76%. For more specific weather details in May, you can check out Yellowknife weather in May. Overall, September is milder and wetter, while May is colder and drier.
In September, temperatures in Yellowknife range from a chilly min of -4°C (25°F) to a max of 22°C (71°F), averaging around 8°C (47°F). The month sees around 28 mm (1.1 in) of precipitation over approximately six days, with a high humidity level of 86%. In contrast, June demonstrates a warmer climate, with temperatures fluctuating between -2°C (29°F) and a comfortable max of 28°C (83°F), averaging 13°C (56°F). The precipitation in June totals 39 mm (1.5 in) over seven days, but the humidity is noticeably lower at 69%. For more detailed insights, check out Yellowknife weather in June.
When comparing the weather in September to that of July, it's evident that July experiences milder temperatures, with an average of 17°C (62°F) and a maximum of 30°C (86°F), while September has a cooler average of 8°C (47°F), peaking at 22°C (71°F). Precipitation is also higher in July, with 56 mm (2.2 in) over 9 days, compared to September's 28 mm (1.1 in) across 6 days. Furthermore, July has lower humidity at 73%, compared to September's higher humidity of 86%. For more detailed information, you can check out Yellowknife weather in July.
In comparing the weather of August and September, we see a notable decline in temperature as summer transitions to fall. August boasts warmer temperatures, with a minimum of 5°C (41°F) and an average high reaching up to 32°C (90°F), whereas September features cooler conditions, starting with a minimum of -4°C (25°F) and a more moderate maximum of 22°C (71°F). Precipitation also varies between the two months; August experiences greater rainfall, totaling 55 mm (2.2 in) over 10 days, compared to September's 28 mm (1.1 in) over 6 days. Additionally, September has a higher average humidity at 86% compared to August's 79%. For more detailed insights, check out the Yellowknife weather in August.
September and October present a notable shift in weather patterns. In September, temperatures range from a minimum of -4°C (25°F) to a maximum of 22°C (71°F), with an average of 8°C (47°F) and relatively lower humidity at 86%. The month experiences 28 mm (1.1 in) of precipitation over about 6 days, signaling the transition of seasons. In contrast, October sees a more substantial drop in temperatures, with a minimum of -13°C (9°F) and a maximum of 12°C (54°F), resulting in an average of 0°C (33°F). The month is slightly drier with 24 mm (0.9 in) of precipitation over 7 days, but the humidity increases to 94%, adding to the chilly air. For more detailed information on conditions in this month, visit Yellowknife weather in October.
September and November present starkly contrasting weather conditions. In September, temperatures range from a minimum of -4°C (25°F) to a pleasant maximum of 22°C (71°F), with an average of 8°C (47°F). The month sees moderate precipitation of 28 mm (1.1 in) over six days, accompanied by a relatively high humidity level of 86%. In contrast, November plunges into frigid temperatures, with a minimum of -31°C (-24°F) and an average temperature of -13°C (8°F), only reaching a maximum of 4°C (40°F). Precipitation decreases slightly to 20 mm (0.8 in) over the same number of days, but humidity climbs to a notable 98%. For a detailed look at November's conditions, you can check Yellowknife weather in November.
In comparing the weather between September and December, we see a dramatic shift in conditions. September experiences a much more moderate temperature range, with minimums around -4°C (25°F) and maximums reaching up to 22°C (71°F). The average temperature is a mild 8°C (47°F), complemented by a relatively low precipitation level of 28 mm (1.1 in) over six days and a humidity level of 86%.
In stark contrast, December brings harsh winter weather, with temperatures plummeting significantly. Minimum temperatures can reach a frigid -42°C (-44°F), while the average hovers around a biting -22°C (-8°F), with maximums barely touching 1°C (34°F). Precipitation decreases to 14 mm (0.6 in) over just four days, but humidity spikes to 100%. For more details on the winter conditions, you can check out Yellowknife weather in December.
As September rolls into Yellowknife, the weather begins to transition from the warmth of summer to the chill of autumn. With average temperatures dipping to a cool 8°C (47°F) and a noticeable increase in humidity at 86%, September sets itself apart from the summer months. The chance of precipitation rises, as the region experiences about 6 days of rain, accumulating to nearly 28 mm (1.1 in). This month not only brings a drop in temperature but also a beautiful change in scenery as the foliage starts to transform, offering a stunning backdrop for outdoor activities. For more insights into the overall climate trends, check out Yellowknife Climate.