Last updated: August 27, 2025
In September, Karlskrona, Sweden experiences a delightful transition into autumn, with average temperatures hovering around 14°C (58°F). Visitors can expect maximum highs reaching 23°C (74°F), alongside cooler nights dipping to a brisk 3°C (38°F). The month is characterized by moderate precipitation, accumulating around 60 mm (2.3 in) over approximately 11 days, contributing to the region's lush landscapes. With an average humidity level of 81%, the air carries a refreshing chill, making it a perfect time for outdoor activities or exploring the city's rich maritime heritage.
In September, Karlskrona begins its gentle transition into autumn, presenting a delightful mix of crisp air and milder temperatures. With a minimum of around 3°C (38°F) and a comfortable average of 14°C (58°F), the city enjoys daytime highs reaching up to 23°C (74°F). This trend marks a noticeable shift from the warm summer months, where temperatures lingered in the high teens and low twenties. As the month progresses, residents and visitors alike can appreciate the refreshing, cooler mornings and pleasantly warm afternoons, making it a perfect time for outdoor activities while embracing the beautiful changing foliage.
In September, Karlskrona experiences a moderately wet transition into autumn, with precipitation totaling 60 mm (2.3 in) over the month and rainfall occurring on 11 days. This marks a slight decrease from the preceding summer months, specifically August's 67 mm (2.7 in), suggesting a gradual shift in weather patterns. The overall trend shows that as the year progresses, precipitation tends to increase, with October often bringing higher totals, peaking at 70 mm (2.8 in). This seasonal rhythm can create a picturesque landscape in Karlskrona, where the onset of fall is marked not only by cooler temperatures but also by a significant increase in rainfall, paving the way for the wet winter months ahead.
As summer gracefully transitions into autumn, September in Karlskrona, Sweden, experiences a slight uptick in humidity, reaching 81%. This marks a notable shift from the drier, warmer months of June and July, which boast humidity levels of just 68%. Following the peak of summer, where humidity starts to gradually increase again in August at 73%, September's moisture content prepares the city for the cooler, damp conditions of October, when humidity rises to 87%. This month serves as a reminder of nature's cyclical rhythm, as the air grows heavier with moisture, foreshadowing the wetter seasons ahead.
As summer transitions into fall, September in Karlskrona, Sweden, sees a noticeable shift in the UV Index, dropping to 5. This represents a moderate exposure category, inviting residents and visitors alike to enjoy the lingering warmth while remaining mindful of sun safety. With a burn time of 30 minutes, it’s a reminder that, although the peak summer months have passed, UV rays can still pose a risk. After a peak in July with an index of 7, September encourages outdoor activities, but with a touch more caution. Embrace the change of seasons and stay informed about UV levels for safe sun enjoyment by checking the comprehensive guide at Karlskrona UV Index.
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In September, Karlskrona enjoys a delightful blend of fading summer and impending autumn, basking in 308 hours of sunshine. This month showcases a notable dip from the sun-soaked July and June, where daylight peaked, yet September still stands out, offering more light than the winter months ahead. As the days grow shorter, sunlight becomes increasingly precious, creating a captivating atmosphere for locals and visitors alike. Despite the waning hours, September remains a wonderful time to appreciate the vibrant hues of nature as it transitions, making every sunbeam count before the chill of October sets in.
In Karlskrona, Sweden, the chances of sunny weather in September reflect a gradual decline as summer transitions into autumn. At 29%, the likelihood of sunshine in September is notably lower compared to the early summer months, with June peaking at 53%. As the year progresses, there is a clear downward trend in sunny days, transitioning from the higher probabilities observed in spring and summer, such as 48% in April and 40% in July. This decline culminates in the autumn months, where October brings even lower sunshine chances at 26%. Despite September's reduced sunshine opportunities, it still offers a pleasant backdrop for early autumn activities—albeit with a growing chance of overcast skies as the month progresses.
As summer fades in Karlskrona, Sweden, September ushers in a gentle transition with approximately 12 hours of daylight. This month marks a noticeable decrease from the sun-soaked days of June, which enjoy the longest daylight at 17 hours, and May, which offers a sumptuous 16 hours. The gradual shortening of days signifies the onset of autumn, yet September still bathes the landscape in a warm glow, allowing for ample time to embrace outdoor activities. In contrast to the light of spring and summer, the daylight in September offers a comforting balance, with a welcoming brightness that lingers, setting the stage for the cozy months ahead.
As September rolls in, Karlskrona experiences a gentle breeze, with an average wind speed of 4.1 m/s (9 mph). This slight dip in wind speed from the summer months signals a transition, as the coastal town shifts from the warmer, windier days of August at 4.5 m/s (10 mph) to the more bracing conditions of autumn. Compared to the earlier months of the year, September’s winds are relatively calm, yet they hold a promise of the brisker gales to come in October and November, both averaging 5.0 m/s (11 mph). This seasonal fluctuation not only enhances the charm of Karlskrona but also invites locals and visitors alike to relish in the serene beauty of early fall along the picturesque coastline.
Weather in Karlskrona varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Karlskrona, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase strikingly different weather patterns. In September, temperatures range from a minimum of 3°C (38°F) to a maximum of 23°C (74°F), with an average of 14°C (58°F), making it a much milder month. The precipitation level is around 60 mm (2.3 in) over 11 days, with humidity at 81%. In contrast, January experiences much colder conditions, with temperatures dipping as low as -10°C (14°F) and only reaching a maximum of 10°C (50°F), averaging just 2°C (36°F). It has slightly less precipitation at 50 mm (2.0 in) over 10 days and higher humidity at 90%. For additional details on January weather, you can visit Karlskrona weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures range from a minimum of 3°C (38°F) to a comfortable average of 14°C (58°F), peaking at 23°C (74°F). The month experiences an average of 60 mm (2.3 in) of precipitation over approximately 11 days, coupled with a humidity level of 81%. In contrast, February is much colder, with temperatures dipping to a minimum of -12°C (11°F) and averaging just 1°C (35°F), reaching a maximum of 11°C (52°F). Although the total precipitation is slightly lower at 58 mm (2.3 in), it is spread over 12 days with a higher humidity of 89%. For more detailed insights, you can check Karlskrona weather in February.
September and March present distinctly different weather patterns. In September, temperatures range from a pleasant 3°C (38°F) at night to a comfortable 23°C (74°F) during the day, with an average of 14°C (58°F). This month also sees around 60 mm (2.3 in) of precipitation over 11 days and a humidity level of 81%. In contrast, March experiences colder conditions, with temperatures dropping as low as -9°C (16°F) and peaking at 13°C (56°F), averaging only 3°C (38°F). Although March has slightly less precipitation at 54 mm (2.1 in) over 13 days, it has a higher humidity level of 88%. For more details on March weather in Karlskrona, visit Karlskrona weather in March.
In comparing the weather of September and April, September typically experiences milder temperatures, with averages around 14°C (58°F) and maximums reaching up to 23°C (74°F), whereas April features cooler conditions, with maximum temperatures averaging 18°C (65°F) and lows dipping to as low as -4°C (24°F). Precipitation is more frequent in September, with around 60 mm (2.3 in) over 11 days, compared to just 28 mm (1.1 in) over 7 days in April. Humidity levels remain similar, with September at 81% and April slightly higher at 82%. For a closer look at weather specifics, you can explore Karlskrona weather in April.
When comparing the weather in September and May, notable differences emerge. September sees slightly warmer temperatures, with minima around 3°C (38°F) and an average of 14°C (58°F), while May is cooler, with a minimum of 0°C (32°F) and an average of 11°C (51°F). Interestingly, both months have similar maximum temperatures, with September peaking at 23°C (74°F) and May at 24°C (75°F). Precipitation levels in September are higher, totaling 60 mm (2.3 in) over 11 days, compared to May's 43 mm (1.7 in) over 10 days. Additionally, September has a higher humidity level of 81%, while May's humidity is more moderate at 72%. For a deeper look into May's climate, check out Karlskrona weather in May.
September and June present notably different weather conditions. In September, the temperature ranges from a chilly 3°C (38°F) at night to a comfortable 23°C (74°F) during the day, averaging around 14°C (58°F). The month experiences more precipitation, totaling about 60 mm (2.3 in) over 11 days, and humidity levels peak at 81%. In contrast, June enjoys milder temperatures, with nighttime lows of 7°C (45°F) and daytime highs reaching up to 26°C (79°F), averaging 16°C (62°F). This month also sees less rainfall, with 37 mm (1.5 in) spread over just 7 days and a lower humidity of 68%. For more detailed insights, you can check Karlskrona weather in June.
In comparing the weather between September and July, it is clear that July tends to be warmer and drier overall. July features a minimum temperature of 10°C (50°F) and an average of 18°C (64°F), reaching a maximum of 28°C (82°F). In contrast, September starts off cooler with a minimum of 3°C (38°F) and averages 14°C (58°F), peaking at 23°C (74°F). While both months experience similar precipitation levels at around 60 mm (2.4 in) in July and 61 mm (2.3 in) in September over 11 days, the humidity is notably higher in September at 81%, compared to July's 68%. For more detailed information, you can check out Karlskrona weather in July.
In contrast to August, September experiences cooler temperatures, with a minimum of 3°C (38°F) compared to August's 9°C (49°F). While the average temperature in August stands at 17°C (63°F), it drops to 14°C (58°F) in September, and September's maximum of 23°C (74°F) is significantly lower than August's peak of 28°C (83°F). Precipitation levels are fairly similar, with September seeing 60 mm (2.3 in) over 11 days, while August has slightly higher precipitation at 67 mm (2.7 in) over 12 days. Notably, September also has a higher humidity level at 81%, compared to August's 73%. For more details, you can visit Karlskrona weather in August.
In September, temperatures are generally milder, with a minimum of 3°C (38°F) and an average high of 23°C (74°F), while October sees a notable drop with minimum temperatures reaching as low as 0°C (33°F) and an average high of only 17°C (62°F). September typically experiences 60 mm (2.3 in) of precipitation over 11 days, but October brings slightly more rain at 70 mm (2.8 in) across 13 days, indicating a transition to wetter conditions. Additionally, humidity levels rise from 81% in September to 87% in October, contributing to the chillier feel of the fall season. For more detailed information, you can check this link: Karlskrona weather in October.
In September, the weather is generally milder, with average temperatures ranging from a cool 3°C (38°F) at night to a warm 23°C (74°F) during the day. This month experiences about 60 mm (2.3 in) of precipitation over 11 days, accompanied by a humidity level of 81%. In contrast, November brings a noticeable chill, with temperatures dropping to a minimum of -5°C (24°F) and peaking at 16°C (60°F). Although slightly less rainfall is recorded at 57 mm (2.2 in) over 12 days, the humidity rises to 89%, contributing to a more overcast and damp feel. For a comprehensive look at November's weather, you can visit Karlskrona weather in November.
In September, the weather in Karlskrona is generally mild, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 23°C (74°F) and an average of 14°C (58°F). The month experiences about 60 mm (2.3 in) of precipitation over 11 days, along with a humidity level of 81%. In contrast, December sees a significant drop in temperatures, with a minimum of -8°C (18°F) and a maximum of 10°C (50°F), averaging just 3°C (38°F). This month also has higher precipitation levels at 69 mm (2.7 in) over 15 days and increased humidity at 88%. For more detailed insights, you can check out Karlskrona weather in December.
As September unfolds in Karlskrona, the transition from the warm embrace of summer to the crispness of autumn becomes evident. With temperatures typically hovering around a comfortable average of 14°C (58°F), this month offers a refreshing shift that can be quite different from the peak summer months. While daytime highs can occasionally reach a pleasant 23°C (74°F), the evenings invite a chill that can drop as low as 3°C (38°F), marking a notable coolness compared to the summer heat. Additionally, September experiences more frequent rain, with 11 days of precipitation adding a touch of moisture to the landscapes. This increase in humidity, reaching around 81%, often creates a serene atmosphere, perfect for enjoying the city’s natural beauty. For those seeking to understand the seasonal rhythms of Karlskrona, further insights can be found in this detailed overview of Karlskrona Climate.