Last updated: August 27, 2025
September in Sundsvall, Sweden, ushers in a gentle shift in climate as the days begin to cool, with maximum temperatures reaching a pleasant 21°C (71°F). The month showcases an average temperature of 10°C (51°F), providing a crisp backdrop as autumn approaches. However, evenings can be chilly, dipping to a minimum of -2°C (29°F). Rainfall is notable, with 64 mm (2.5 in) accumulated over 13 days, contributing to the region's lush scenery. The air is particularly humid at 89%, creating a fresh, invigorating atmosphere that characterizes this transitional month in Sundsvall.
As September fades into early autumn, Sundsvall, Sweden experiences a notable shift in temperatures, reflecting the gradual departure from the warm summer months. The month opens with minimum temperatures around -2°C (29°F), providing a crispness that hints at the upcoming chill. As the days progress, the average temperature hovers at a comfortable 10°C (51°F), making it a pleasant time for outdoor activities amidst the changing foliage. The highs can reach a mild 21°C (71°F), offering a last taste of warmth before the colder months set in. This transitional period is perfect for enjoying the beauty of nature as it prepares for the winter ahead, with cooler nights paving the way for cozy evenings indoors.
In September, Sundsvall experiences a notable increase in precipitation, receiving 64 mm (2.5 in) of rainfall over 13 days, marking a transition into the wetter autumn months. This uptick follows the relatively humid summer, where August recorded 74 mm (2.9 in), and showcases a consistent pattern as the region prepares for the heavier rains of October, which typically averages 89 mm (3.5 in). The rainy trend from the summer into early autumn indicates a gradual shift in weather patterns, preparing the landscape for the vibrant fall foliage while also foreshadowing the brisk chill of winter. As Sundsvall welcomes September's rain, the days grow shorter and the air becomes refreshingly crisp, setting the stage for the seasonal change.
In Sundsvall, Sweden, September marks a notable shift in humidity levels, settling at 89%. As summer fades, the air begins to embrace the freshness of fall, reflecting a slight uptick from August's 86%. This trend showcases the transition from the warmer months, where humidity peaked in July at 80%, to the cooler months ahead. Significantly, the gradual increase in humidity through the autumn months continues into October and November, emphasizing the region's characteristic dampness during this season. Overall, September serves as a bridge between the vibrant summer and the crisp autumn, providing a lush and refreshing atmosphere in Sundsvall.
In September, Sundsvall experiences a moderate UV Index of 3, indicating it’s time to savor the late summer sun while remaining cautious. With a burn time of around 30 minutes, individuals are encouraged to take protective measures during peak sun hours. This month marks a notable transition, as UV levels begin to decline from the summer highs of 6 in July and June, reflecting a gradual shift toward autumn. As the days shorten and temperatures cool, the lower index signifies a more forgiving sun, yet vigilance remains essential for outdoor activities. For more detailed insights into UV levels in Sundsvall throughout the year, check out the Sundsvall UV Index.
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As September rolls into Sundsvall, Sweden, the transition from summer to autumn brings a gentle decline in daylight, with the city basking in 282 hours of sunlight. This month marks a notable shift, as it follows the sun-drenched peak of July, which boasts the highest sunshine at 499 hours. Despite this decrease, September still offers significantly more light than the dreariness of winter months ahead, such as November with just 115 hours. The gradual dip in sunlight from the vibrant 491 hours of June serves as a reminder of the cyclical beauty of nature, where the warm days gradually yield to cooler evenings, creating a perfect backdrop for enjoying the rich colors of the changing leaves. There's an inviting charm in the crisp air and softer light, making September a delightful time to experience the enchanting landscape of Sundsvall.
In Sundsvall, Sweden, September marks a transitional period, with a 26% chance of sunny weather gracing the month. As summer wanes, the likelihood of sunny days dips compared to the peak of July, which boasts a robust 51% chance. The shift from August’s 31% further signifies the encroaching autumn chill. Although September is less likely to offer bright, sunlit days than its summer predecessors, it still presents a charming backdrop of near-sunny days, perfect for enjoying the lingering warmth of the season before winter sets in.
As summer transitions into fall, September in Sundsvall, Sweden marks a shift in daylight hours, bringing about 12 hours of light each day. This decrease follows a bright summer peak in June, where daylight stretched to an impressive 19 hours. The month showcases a gradual reduction from the vibrant daylight of August, which boasts 15 hours, hinting at the onset of autumn. With each passing month, the trend continues, as the daylight dwindles down to 9 hours in October, and eventually to the shorter, darker days of winter. This rhythm of daylight reflects nature's cyclical beauty, inviting residents to cherish the lingering warmth of September before embracing the embracing the chill of the colder seasons ahead.
In Sundsvall, Sweden, September brings a gentle embrace of wind, with an average speed of 3.3 m/s (7 mph). As summer fades, the blustery whispers of early fall continue the trend observed throughout the year, where wind speeds hover around the 3 to 4 m/s mark. Interestingly, September's winds are slightly stronger than the calm summer months of June and July, where speeds dip to 2.7 and 2.9 m/s, respectively. This subtle increase signals a transition to the more dynamic months ahead, with October anticipated to pick up pace again at 3.7 m/s. Overall, September's breezy conditions invite both locals and visitors to enjoy the shifting season, as nature begins its annual transformation.
Weather in Sundsvall varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Sundsvall, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of September and January, a stark contrast emerges. September features milder temperatures, ranging from a minimum of -2°C (29°F) to a comfortable average of 10°C (51°F) and a maximum of 21°C (71°F). With 64 mm (2.5 in) of precipitation over 13 days and a humidity level of 89%, it is a relatively wet month. In contrast, January experiences much harsher conditions, with temperatures plummeting to a minimum of -28°C (-18°F) and an average of -5°C (24°F), peaking at just 8°C (47°F). Although January has slightly less precipitation at 55 mm (2.1 in) over 9 days, the humidity is notably higher at 97%, contributing to the biting cold. For a more detailed look at January weather, visit Sundsvall weather in January.
September and February present striking contrasts in weather. In September, temperatures range from a chilly -2°C (29°F) at night to a pleasant 21°C (71°F) during the day, with an average of 10°C (51°F). The month experiences around 64 mm (2.5 in) of precipitation over 13 days, with humidity lingering at 89%. In stark contrast, February is much colder, featuring minimum temperatures plummeting to -22°C (-7°F) and a daytime maximum of only 8°C (47°F), with an average temperature of -5°C (23°F). This winter month accumulates about 44 mm (1.7 in) of precipitation spread over 8 days, while humidity rises to a high of 95%. For more details on February weather, check Sundsvall weather in February.
When comparing the weather in September and March, noticeable differences emerge in temperature and precipitation. September experiences milder temperatures, with a minimum of -2°C (29°F) and an average of 10°C (51°F), peaking at a comfortable 21°C (71°F). In contrast, March is much colder, featuring a minimum of -23°C (-10°F) and an average of -1°C (30°F), with a maximum of only 13°C (55°F). Precipitation levels are slightly higher in September at 64 mm (2.5 in) over 13 days, compared to March's 45 mm (1.8 in) over 9 days. Humidity also remains high in both months, reaching 89% in September and 92% in March. For more detailed information on March weather, visit Sundsvall weather in March.
When comparing the weather in September and April, notable differences emerge in temperature and precipitation patterns. September enjoys milder temperatures with an average of 10°C (51°F), while April is chillier, averaging only 3°C (38°F), despite both months reaching a maximum of 21°C (70°F). In terms of precipitation, September sees more rainfall, accumulating 64 mm (2.5 in) over 13 days, compared to April's lighter 30 mm (1.2 in) spread across just 8 days. Humidity levels are fairly similar, with September at 89% and April slightly lower at 86%. For more detailed insights on April weather, you can check Sundsvall weather in April.
September and May present distinct weather characteristics in terms of temperature, precipitation, and humidity. In September, temperatures range from a chilly minimum of -2°C (29°F) to a maximum of 21°C (71°F), with an average of 10°C (51°F). The month sees an average precipitation of 64 mm (2.5 in) over 13 days, accompanied by high humidity at 89%. In contrast, May typically features slightly cooler temperatures, with a minimum of -4°C (25°F), an average of 9°C (48°F), and a max of 27°C (81°F). Precipitation is lower in May, totaling 37 mm (1.5 in) across 9 rainy days and a humidity level of 80%. For a detailed look at May weather in Sundsvall, visit Sundsvall weather in May.
When comparing the weather in September and June, notable differences emerge in temperature and humidity. September tends to be cooler, with average temperatures around 10°C (51°F) and a maximum of 21°C (71°F), while June enjoys a much warmer average of 15°C (58°F), peaking at 32°C (90°F). Additionally, September experiences higher humidity levels at 89% compared to June's 76%, contributing to a more damp feeling. Both months see a similar amount of precipitation, with September recording 64 mm (2.5 in) over 13 days and June slightly less at 57 mm (2.3 in) over 9 days. For more detailed information about June weather, you can visit Sundsvall weather in June.
In comparing the weather between September and July, we see notable differences in temperature and humidity. September features a cooler climate, with average temperatures ranging from a low of -2°C (29°F) to a high of 21°C (71°F), while July enjoys a much warmer range, starting at 4°C (40°F) and peaking at 30°C (87°F). Additionally, September experiences a higher average humidity at 89%, compared to July's 80%, contributing to a different sensation of warmth. Precipitation levels are also quite distinct; September sees about 64 mm (2.5 in) over 13 days, whereas July has slightly more at 77 mm (3.0 in) across 11 days. For a closer look at July weather specifics, you can check Sundsvall weather in July.
In comparing the weather between August and September, a noticeable shift occurs as summer transitions to autumn. August boasts warmer temperatures, with a minimum of 2°C and an average of 15°C, peaking at 27°C. In contrast, September's temperatures drop, with a minimum of -2°C and an average of just 10°C, reaching a maximum of 21°C. Precipitation is slightly higher in August at 74 mm compared to September's 64 mm, although both months see rainfall on 13 days. Humidity remains relatively consistent, with September experiencing a marginally higher level at 89% compared to August's 86%. For more detailed information, you can visit Sundsvall weather in August.
September and October present a notable shift in weather conditions. In September, temperatures range from a minimum of -2°C (29°F) to a maximum of 21°C (71°F), with an average of 10°C (51°F). During this month, the region experiences approximately 64 mm (2.5 in) of precipitation over 13 days and maintains a relatively high humidity level of 89%.
In contrast, October sees a drop in average temperatures, with minimums reaching -8°C (18°F) and an overall average of 5°C (42°F), while the maximum temperature is slightly lower at 20°C (68°F). Precipitation increases to 89 mm (3.5 in) over 14 days, and humidity rises to 93%. This transition from September to October marks a significant cooling and wetting trend, characteristic of the fall season. For more details, check out Sundsvall weather in October.
In September, the weather tends to be milder with a minimum temperature of -2°C (29°F) and an average of 10°C (51°F), peaking at a maximum of 21°C (71°F). The month experiences about 64 mm (2.5 in) of precipitation over 13 days, while humidity levels hover around 89%. In contrast, by November, temperatures drop significantly, with a minimum of -15°C (5°F), an average of 0°C (32°F), and a maximum of 13°C (56°F). November brings less precipitation at 47 mm (1.9 in) over 10 days, but humidity rises slightly to 94%. For more detailed information, you can check out Sundsvall weather in November.
September weather in Sundsvall exhibits a moderate range of temperatures, with minimums around -2°C (29°F) and maximums reaching up to 21°C (71°F), bringing an average of 10°C (51°F). Rainfall is relatively light at 64 mm (2.5 in) over approximately 13 days, paired with a humidity level of 89%. In contrast, December introduces much colder conditions, where minimum temperatures plummet to -22°C (-7°F) and maximums hover around 7°C (46°F), resulting in a chilling average of -3°C (27°F). The month experiences slightly higher precipitation at 76 mm (3.0 in) across the same number of rainy days, along with increased humidity at 96%. For more detailed insights on the December weather, you can refer to Sundsvall weather in December.
September in Sundsvall marks a significant transition as summer fades into autumn, bringing cooler temperatures and increased precipitation. With an average temperature that dips to a refreshing 10°C (51°F), the warmth of previous months gives way to crisp air. The 64 mm (2.5 in) of rainfall across approximately half the month highlights the onset of the wetter season, contributing to the 89% humidity that envelops the region. This shift not only accentuates the vibrant colors of the landscape but also invites cozy activities indoors as the days shorten. For more about the climate patterns throughout the year, check out Sundsvall Climate.