Last updated: August 27, 2025
September in Sigtuna, Sweden offers a fascinating transition into autumn, characterized by a temperature range that spans from a pleasant maximum of 27°C (80°F) to a chilly minimum of -1°C (30°F). The average temperature hovers around a comfortable 13°C (55°F), making it an ideal time for outdoor exploration. However, visitors should prepare for the occasional rain, as the month sees around 51 mm (2.0 in) of precipitation over 8 days. With humidity levels at a notable 85%, the atmosphere carries a crisp freshness, perfect for enjoying the vibrant fall scenery that Sigtuna has to offer.
As September unfolds in Sigtuna, Sweden, the chill of winter begins to wane, making way for a refreshing transition. With a minimum temperature dipping just below freezing at -1°C (30°F), residents can expect crisp mornings, while the average settles comfortably at 13°C (55°F). The maximum temperature can reach a pleasant 27°C (80°F), creating a delightful contrast as days gradually shorten. This month marks a significant shift from the summer highs, indicating the encroachment of autumn. While September retains a hint of summer’s warmth, it heralds the cooler temperatures to follow, painting the landscape with vibrant fall colors and inviting outdoor exploration before winter’s return.
In September, Sigtuna experiences a moderate shift in precipitation, recording 51 mm (2.0 in) over 8 days. This amount represents a slight decrease from the more rainfall-drenched August, which saw 74 mm (2.9 in) across 12 days. As autumn approaches, the overall trend suggests a gradual transition into wetter months, with precipitation often peaking in October at 68 mm (2.7 in). The consistent uptick in rainfall from summer into fall signifies a crucial shift in the region's climate pattern, setting the stage for the crisp and often drizzly days that define Sigtuna's picturesque autumn landscape.
In September, Sigtuna experiences a noticeable uptick in humidity, settling at a comfortable 85%. This increase marks a transition from the drier summer months, where humidity dipped to its lowest point in July at 74%. As autumn approaches, the air becomes more saturated, creating a refreshing contrast to the preceding warm season. Interestingly, the humidity levels in September closely resemble those of April, highlighting a seasonal rhythm where spring and early autumn share similar atmospheric characteristics. With humidity rising again into the early winter months, such as in October at 89%, it’s clear that Sigtuna's climate embraces a moist embrace as it transitions from summer's warmth to fall's crispness.
In September, Sigtuna, Sweden experiences a UV Index of 4, categorizing exposure as moderate with a burn time of 30 minutes. This marks a slight decline from the peak summer months of June and July, where the UV Index reached 7 and skin sensitivity intensified. As the days grow shorter and temperatures begin to cool, the UV levels also lower, signaling a transition into the autumn months. However, with September still offering a respectable UV Index, it's a good reminder to remain sun-aware when spending time outdoors. For more detailed information, visit the Sigtuna UV Index.
UV Risk Categories
In Sigtuna, Sweden, September bathes the landscape in a warm embrace, with an impressive 301 hours of sunshine illuminating the transition from summer to autumn. This month showcases a notable decline in daylight compared to the sun-soaked heights of July, which boasts 483 hours, but still holds its ground as a vibrant time of year. As summer fades, the gradual decrease in sunshine hours hints at the impending chill of October's 207 hours, creating a perfect backdrop for enjoying the beautiful fall foliage. Overall, September offers a golden opportunity to soak in the remaining warmth of the season before the long, cozy nights claim the spotlight.
As September rolls into Sigtuna, Sweden, the likelihood of sunny weather takes a dip, with a 25% chance of sunshine. This marks a significant decrease from the 54% peak in July, indicating that summer's vibrancy is waning as autumn approaches. After the warmth of the summer months, where sunny days reign supreme, September ushers in a more unpredictable climate. While it's not the sunniest month, it still offers bursts of pleasant weather, reminiscent of the fading summer. As leaves begin to turn, residents and visitors can enjoy the early days of fall, even if the sun isn't always shining bright.
As summer fades into autumn, September in Sigtuna, Sweden, offers a gentle shift in daylight duration. With 12 hours of daylight, the month marks a transition from the sun-drenched days of July and August, which boasted up to 17 and 15 hours respectively. The daylight begins to wane, reminiscent of the gradual decline seen in the months leading towards winter. This pattern emphasizes the rhythm of the seasons, as the length of daylight iteratively decreases, with October providing even less at 10 hours. Nature’s gradual dimming not only signals the approach of colder days but also presents a beautiful opportunity to enjoy the stunning autumnal colors during these serene daylight hours.
As summer fades into autumn in Sigtuna, September welcomes a gentle breeze with an average wind speed of 3.3 m/s (7 mph). This marks a slight increase from the calmer months of June and July, where the winds dipped to 2.6 m/s (6 mph) and 2.9 m/s (6 mph) respectively. The subtle uptick in wind speed hints at the seasonal transition, preparing the landscape for the brisk October winds that average 4.0 m/s (9 mph). Overall, September's breezy charm not only invigorates the air but also bridges the serene stillness of summer to the more dynamic gusts of fall, creating a refreshing backdrop for Sigtuna's picturesque autumn scenery.
Weather in Sigtuna varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Sigtuna, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather conditions. In September, temperatures vary from a minimum of -1°C (30°F) to a pleasant maximum of 27°C (80°F), providing an average of 13°C (55°F). This month experiences about 51 mm (2.0 in) of precipitation over approximately 8 days, with humidity levels at a relatively comfortable 85%. In contrast, January is significantly colder, with temperatures ranging from a minimum of -23°C (-10°F) to a maximum of 10°C (51°F), averaging -1°C (31°F). Although January has slightly less precipitation at 34 mm (1.4 in) over 7 days, the humidity rises to 90%, creating a biting chill. For more detailed insights on Sigtuna weather in January, the comparisons are striking, highlighting the shift from the mildness of early autumn to the harshness of mid-winter.
September and February present quite contrasting weather conditions. In September, temperatures range from a chilly minimum of -1°C (30°F) to a pleasant maximum of 27°C (80°F), with an average of 13°C (55°F). The month sees 51 mm (2.0 in) of precipitation over about 8 days and maintains a humidity level of 85%. In stark contrast, February boasts much colder temperatures, with lows plummeting to -17°C (1°F) and a maximum of only 12°C (53°F), averaging around -1°C (30°F). This winter month experiences less precipitation at 32 mm (1.2 in) over 7 days, yet the humidity remains high at 88%. For more detailed information, you can read Sigtuna weather in February.
In comparing the weather between September and March, we see notable differences in temperature and general conditions. September enjoys a milder climate with average temperatures around 13°C (55°F) and a maximum of 27°C (80°F), while March is significantly colder, with an average of just 1°C (35°F) and a maximum of 18°C (65°F). Precipitation levels are relatively close, with September receiving 51 mm (2.0 in) and March slightly less at 41 mm (1.6 in), both occurring across 8 days. Humidity remains high in both months, with September at 85% compared to March's 89%. For more detailed insights, you can check Sigtuna weather in March.
The weather in September is generally milder than in April, with temperatures ranging from a minimum of -1°C (30°F) to a pleasant maximum of 27°C (80°F). In contrast, April experiences colder averages, with temperatures ranging from a low of -9°C (17°F) to a high of 24°C (76°F). While September sees slightly more precipitation with 51 mm (2.0 in) over 8 days, April is relatively drier with 28 mm (1.1 in) over 7 days. Both months maintain a high humidity level of 85%, contributing to a damp atmosphere. For a closer look at April weather patterns, visit Sigtuna weather in April.
In comparing the weather of September and May, a few key differences emerge. September typically experiences a milder average temperature of 13°C (55°F) with a maximum reaching 27°C (80°F), while May tends to be slightly cooler, with an average of 11°C (52°F) and a maximum of 30°C (85°F). Precipitation levels in both months are fairly similar, with September receiving 51 mm (2.0 in) over about 8 days and May slightly higher at 56 mm (2.2 in) across 10 days. Additionally, September has a higher humidity of 85%, compared to May's 77%, making September feel a bit more muggy overall. For more detailed insights, you can check Sigtuna weather in May.
In comparing the weather between September and June, we see notable differences in temperature and humidity levels. September experiences a broader range, with temperatures ranging from a chilly minimum of -1°C (30°F) to a comfortable maximum of 27°C (80°F), averaging around 13°C (55°F). It also tends to be quite humid, with humidity levels reaching 85%. In contrast, June presents more consistently warm conditions, with minimum temperatures of 3°C (37°F) and maximums climbing up to 31°C (89°F), averaging around 17°C (63°F). Although June has slightly higher precipitation at 58 mm (2.3 in) over the same number of rainy days as September, it feels drier due to lower humidity levels at 76%. For a closer look at the specifics of June weather in Sigtuna, you can check out Sigtuna weather in June.
In comparing the weather between September and July, we can observe some notable differences. September tends to be cooler, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 27°C (80°F), and an average temperature of 13°C (55°F). In contrast, July enjoys warmer temperatures, with a minimum of 6°C (44°F), an average of 18°C (65°F), and highs reaching up to 32°C (91°F). Additionally, September experiences relatively high humidity at 85% and 51 mm (2.0 in) of precipitation over 8 days, while July, although slightly wetter with 53 mm (2.1 in) over 10 days, has lower humidity levels of 74%. For more detailed information on July weather, you can check Sigtuna weather in July.
In September, temperatures experience a notable drop compared to August, with minimums dipping to -1°C (30°F) and average highs reaching only 27°C (80°F), while August features warmer averages, including a minimum of 4°C (39°F) and maximums peaking at 31°C (88°F). Additionally, September sees higher humidity levels at 85% compared to August's 77%, contributing to a cooler feel overall. Precipitation also varies, as September receives 51 mm (2.0 in) over 8 days, while August has a greater total of 74 mm (2.9 in) across 12 days of rain. For those interested in more detailed weather conditions, you can check Sigtuna weather in August.
September and October present a noticeable shift in weather characteristics. September boasts milder temperatures with a minimum of -1°C (30°F), an average of 13°C (55°F), and a maximum of 27°C (80°F), making it a generally warmer month. In contrast, October sees a drop in temperatures, featuring a minimum of -4°C (25°F), an average of 8°C (46°F), and a maximum of 19°C (67°F). Rainfall also increases in October, with 68 mm (2.7 in) of precipitation spread across 12 days, compared to September's 51 mm (2.0 in) over 8 days. Humidity rises slightly as well, reaching 89% in October versus 85% in September. For those curious about more details, check out Sigtuna weather in October.
September and November present contrasting weather conditions. In September, temperatures range from a chilly minimum of -1°C (30°F) to a comfortable maximum of 27°C (80°F), with an average of 13°C (55°F). The month experiences 51 mm (2.0 in) of precipitation over 8 days, coupled with a relatively high humidity of 85%. By November, the weather shifts dramatically, as the minimum temperature drops to -13°C (9°F) and the average plummets to just 4°C (39°F), with a maximum of 15°C (59°F). Precipitation decreases slightly to 42 mm (1.6 in), but it occurs over 9 days, and humidity rises to 90%. For more details on November conditions, you can check Sigtuna weather in November.
In September, the weather is relatively mild, with average temperatures ranging from a chilly 1°C (30°F) at night to a warm 27°C (80°F) during the day. The month typically sees around 51 mm (2.0 in) of precipitation over about 8 days, with humidity averaging 85%. In contrast, December brings much colder conditions, with temperatures dropping to an average of 0°C (33°F), and nighttime lows plummeting to -18°C (1°F). Rainfall increases slightly to 56 mm (2.2 in), spread over 13 days, and humidity remains high at 87%. For those interested in more detailed December weather patterns, visit Sigtuna weather in December.
As September unfolds in Sigtuna, it brings a unique transition from the warm embrace of summer to the cool onset of autumn. With temperatures averaging a comfortable 13°C and the occasional peak at 27°C, this month offers a delightful blend of mild warmth while hinting at the crispness to come. Unlike the drier summer months, September introduces a bit more humidity, complemented by an increase in precipitation days, making the landscape lush yet occasionally damp. This shift sets the scene for a vibrant tapestry of autumn colors, encouraging exploration amidst cooler breezes. For those curious about the effects of changing seasons on Sigtuna’s weather patterns, check out the detailed insights available at Sigtuna Climate.