September Weather in Karlstad, Sweden

Last updated: August 27, 2025

In September, Karlstad, Sweden experiences a delightful transition into autumn, showcasing a range of temperatures that average around 12°C (54°F), with highs reaching a pleasant 24°C (75°F) and lows dipping to 0°C (33°F). This month also sees a relatively humid atmosphere, with humidity levels at an impressive 86%. Rainfall is typical, as 78 mm (3.1 in) of precipitation falls over 12 days, providing a refreshing touch to the landscape. Whether you’re enjoying the crisp air or the gentle showers, September in Karlstad is a captivating blend of warmth and freshness.

September Temperature in Karlstad

In September, Karlstad experiences a refreshing transition from the warm summer days to the crispness of autumn. With minimum temperatures hovering around 0°C (33°F) and averages settling at a comfortable 12°C (54°F), locals enjoy a pleasant climate perfect for outdoor activities. The maximum temperature can reach up to 24°C (75°F), offering a final taste of summer warmth before the chill of October sets in. This month stands out as a time of balance, where the city basks in mild weather adorned with the early hues of fall, making it an ideal period for both exploration and relaxation.

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

The chart illustrates September temperature patterns in Karlstad, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Karlstad, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec313035435262646154463832
Data source: Temperature data for Karlstad generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Karlstad

In September, Karlstad experiences a notable shift as summer transitions into autumn, marked by an average precipitation of 78 mm (3.1 in) over approximately 12 days. This represents a slight decrease from the previous month, yet still highlights a significant amount of rainfall as the region prepares for cooler weather. Compared to August's 86 mm (3.4 in), September's totals emphasize the seasonal shift while maintaining a robust level of moisture during the month. This trend continues into October, often bringing more rain, but September remains pivotal in signaling the end of summer's high precipitation days and the onset of a wetter autumn period in Karlstad.

September Precipitation Trends in Karlstad

The chart displays monthly precipitation patterns in Karlstad, 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. In Karlstad, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec484749316460698678866874
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Karlstad

In September, Karlstad experiences a notable shift in humidity, settling at 86% after the gradually decreasing levels of the summer months. Following a peak of 77% in August, the rise in humidity this month signals the onset of fall, as the air begins to retain more moisture in preparation for the colder months ahead. This spike is reflected in the steadily increasing trend as the year progresses toward winter, with humidity reaching 91% in October and peaking again at 94% come December. Overall, the data reveals a clear pattern: while the summer months tend to enjoy more moderate humidity, the transition into autumn and winter brings a return to the higher humidity levels characteristic of Karlstad's climate.

September Average Humidity in Karlstad

This chart illustrates the average monthly humidity levels in Karlstad, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Karlstad is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec94%92%89%81%72%68%70%77%86%91%93%94%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Karlstad

In September, Karlstad experiences a shift towards moderate UV exposure, with a UV Index of 4 and a necessary burn time of 30 minutes. This month marks a gradual decline from the high summer levels, where June and July peaked at 7, prompting extra caution during outdoor activities. As days shorten and temperatures cool, the UV index dips, but it remains essential to be mindful of sun exposure, especially on clear days. Transitioning from the intense summer rays, September's UV conditions still warrant attention for anyone venturing outside. For those looking to monitor the UV Index throughout the year, more detailed information can be found here: Karlstad UV Index.

Maximum UV Index Levels in Karlstad for September

The chart shows the monthly maximum UV Index (UVI) for Karlstad 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. In September, the maximum UV index in Karlstad typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec113457754211
Data source: Karlstad 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 Karlstad

September in Karlstad, Sweden, marks the transition from the vibrant summer months to the cooler embrace of autumn. With 284 hours of sunshine, this month continues to glow with a generous but dwindling light, following the peak of 473 hours in July. As the days grow shorter, there's a noticeable decline from the sunny splendor of summer, yet September still offers more brightness than the colder months ahead. This progressive decrease in sunlight lays the groundwork for cozy fall evenings, inviting locals and visitors alike to savor the warm hues of the season before winter's chill arrives.

Monthly Sunshine Duration in Karlstad: September Highlighted

The September sunshine duration represents the total number of hours Karlstad 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.
JanFebMarAprMayJunJulAugSepOctNovDec78h164h270h371h426h464h473h401h284h213h122h79h
Data source: Karlstad September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Karlstad During September

In Karlstad, Sweden, the likelihood of sunny weather takes a notable dip in September, with chances of sunshine falling to 28%. This marks a significant drop from the sunnier summer months, where July and August boast higher percentages of 45% and 34% respectively. As the early autumn sets in, the trend shows a gradual decrease in sunshine, continuing into the cooler months, such as October and November, which both hover around 27% and 23%. While September might not promise beach days, its mild climate offers a serene backdrop, making it a great time for outdoor activities amidst the changing leaves.

Percentage of Sunny Days in September in Karlstad

The chart illustrates the percentage of sunny days in Karlstad 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 Karlstad experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec25%41%41%50%33%41%45%34%28%27%23%28%
Data source: Karlstad September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Karlstad in September

As summer fades into autumn, September in Karlstad, Sweden, sees a noticeable shift with 12 hours of daylight—a gentle decline from the sun-soaked days of summer, where daylight peaked at 18 hours in June. This month marks a transition, as the warm glow of late summer gives way to shorter days, reminiscent of the 14 hours enjoyed in April and the vibrant 17 hours in May. The steady decrease in daylight continues into the fall, leading to October's modest 10 hours. As the seasons change, Karlstad's landscape transforms too, inviting residents to relish the crisp air and golden hues of the autumn months.

Average Daylight Hours in Karlstad for September

The chart illustrates the variation in daylight duration in Karlstad throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec6h 57m9h 13m11h 52m14h 33m17h 3m18h 28m17h 42m15h 24m12h 46m10h 6m7h 36m6h 10m
Data source: Karlstad daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Karlstad

In September, the winds of Karlstad, Sweden begin to transition as summer wanes, with an average speed of 3.3 m/s (7 mph), slightly up from the calmer summer months. As the days shorten and temperatures drop, September maintains a steady breeze reminiscent of the earlier months, which lingered around similar figures, peaking at 3.7 m/s (8 mph) in April. The month sets the stage for a noticeable uptick in windiness as autumn approaches, indicated by a jump to 4.1 m/s (9 mph) in October. As the gentle winds rustle through the trees, they signal the arrival of a new season, inviting both locals and visitors to embrace the beauty of nature's transformation.

Average September Wind Speed in Karlstad

The chart displays monthly wind speed patterns in Karlstad, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.13.43.53.73.02.92.83.13.3 m/s4.13.33.1
Data source: Karlstad September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Karlstad Compares to Other Months

Weather in Karlstad varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Karlstad, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present two distinct weather profiles. September enjoys mild temperatures, with daily averages around 12°C (54°F) and maximums reaching 24°C (75°F), while the weather is relatively humid at 86%. In contrast, January is much colder, with average temperatures dropping to -1°C (31°F) and maximums rarely exceeding 9°C (49°F). The winter month sees less precipitation at 48 mm (1.9 in) over just 8 days, but the humidity peaks at a chilly 94%. For a deeper look at how January weather unfolds in Karlstad, check out Karlstad weather in January.

September and February present a stark contrast in weather conditions. September boasts milder temperatures, with averages around 12°C (54°F) and maximums reaching 24°C (75°F), making it a pleasant transition into autumn. In contrast, February is much colder, with average temperatures plummeting to -1°C (30°F) and minimums dipping as low as -15°C (5°F). While September experiences higher precipitation at 78 mm (3.1 in) over 12 days, February sees less rainfall, totaling 47 mm (1.9 in) over 9 days. Additionally, February's humidity is somewhat elevated at 92%, compared to September's 86%, contributing to the chilly atmosphere typical of winter. For a more detailed insight into February weather, you can check out Karlstad weather in February.

In September, weather in Karlstad features milder temperatures, with averages around 12°C (54°F) and highs reaching up to 24°C (75°F), making it a comfortable transition into autumn. The month experiences relatively high humidity at 86% and sees approximately 78 mm (3.1 in) of precipitation over about 12 days. In contrast, March brings a much colder climate with average temperatures of just 2°C (35°F) and nights dipping as low as -14°C (7°F). Precipitation levels are lower at 49 mm (1.9 in) across 9 days, but humidity remains high at 89%. For more detailed insights into March's weather patterns, check Karlstad weather in March.

September and April showcase contrasting weather patterns, with September generally being warmer and wetter. In September, temperatures range from a chilly 0°C (33°F) at night to a comfortable 24°C (75°F) during the day, accompanied by an average of 78 mm (3.1 in) of rain over about 12 days. The humidity is also higher, sitting at 86%. In contrast, April sees cooler temperatures, with nighttime lows dropping to -9°C (17°F) while daytime highs reach 22°C (72°F). This month is much drier, with only 31 mm (1.2 in) of precipitation over approximately 7 days and a humidity level of 81%. For more detailed information, you can check Karlstad weather in April.

In comparing the weather between September and May, we can observe a few distinct differences. September boasts a wider temperature range, with minimums around 0°C (33°F) and maximums reaching 24°C (75°F), whereas May starts with slightly cooler minimums at -2°C (29°F) but can warm up to a maximum of 29°C (85°F). Precipitation in September is somewhat higher at 78 mm (3.1 in) compared to May’s 64 mm (2.5 in), despite both months experiencing rain on roughly 12 days. Additionally, humidity levels are more pronounced in September at 86%, while May enjoys a relatively lower humidity of 72%. For a more detailed look at the weather specifics, you can check out Karlstad weather in May.

In September, the weather tends to be cooler and more variable compared to June. The minimum temperature in September drops to 0°C (33°F), with an average of 12°C (54°F) and a maximum of 24°C (75°F). In contrast, June offers warmer temperatures, starting from a minimum of 5°C (40°F) and reaching an average of 17°C (63°F) and a peak of 31°C (87°F). Additionally, September experiences higher humidity at 86% and more precipitation, with 78 mm (3.1 in) over 12 days, while June has a more moderate humidity level of 68% and less rainfall at 60 mm (2.4 in) over 11 days. For a detailed look at June weather specifics, visit Karlstad weather in June.

In comparing the weather of September and July, it is evident that July enjoys warmer temperatures, with highs averaging 33°C (91°F) and a more comfortable minimum of 7°C (45°F). In contrast, September features cooler conditions, ranging from a minimum of 0°C (33°F) to a maximum of 24°C (75°F), with an average of just 12°C (54°F). Additionally, while July has slightly less precipitation at 69 mm (2.7 in) over 11 days, September experiences more rain, with 78 mm (3.1 in) over 12 days, and a notably higher humidity level of 86% compared to July’s 70%. For more detailed insights into July weather, you can visit Karlstad weather in July.

In comparing the weather between September and August, September showcases cooler temperatures with a minimum of 0°C (33°F), an average of 12°C (54°F), and a maximum of 24°C (75°F), while August offers warmer conditions with a minimum of 6°C (44°F), an average of 16°C (62°F), and a maximum reaching 32°C (89°F). Precipitation is slightly lower in September, totaling 78 mm (3.1 in) over 12 days, compared to August's 86 mm (3.4 in) across 15 days. Interestingly, September has a higher humidity level at 86%, compared to 77% in August. For more detailed information about August weather, you can visit Karlstad weather in August.

September and October present a notable shift in weather patterns. September features a milder temperature range with minimums of 0°C (33°F) and maximums reaching up to 24°C (75°F), while October dips to a minimum of -4°C (26°F) and a maximum of 19°C (66°F). Precipitation slightly increases from 78 mm (3.1 in) in September to 85 mm (3.4 in) in October, along with a rise in the number of rainy days from 12 to 13. Additionally, humidity levels are higher in October, reaching 91% compared to 86% in September. This transition marks the arrival of cooler, wetter conditions as autumn progresses. For more detailed weather insights, you can check Karlstad weather in October.

In September, the weather in Karlstad is relatively mild, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 24°C (75°F) and an average of 12°C (54°F). During this month, precipitation is moderate at 78 mm (3.1 in) over about 12 days, accompanied by a humidity level of 86%. In contrast, November brings a significant drop in temperatures, with a minimum of -10°C (15°F) and an average of just 3°C (38°F), peaking at 15°C (59°F). Though the total precipitation in November is slightly lower at 68 mm (2.7 in), it still occurs over roughly 12 days, with humidity increasing to 93%. For a more detailed overview of the weather in November, check Karlstad weather in November.

September and December present starkly contrasting weather patterns. In September, temperatures range from a mild 0°C (33°F) at night to a comfortable high of 24°C (75°F) during the day, accompanied by an average temperature of 12°C (54°F). The month sees around 78 mm (3.1 in) of precipitation over approximately 12 days, with humidity levels at a relatively lower 86%. In contrast, December experiences far colder conditions, with temperatures dipping to a minimum of -17°C (2°F) and a maximum of just 9°C (49°F), averaging around 0°C (32°F). Precipitation remains similar at 74 mm (2.9 in), but falls over more days—about 14 in total—leading to higher humidity levels of 94%. For a more detailed look at what to expect, check out Karlstad weather in December.

Compare Karlstad's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Karlstad

September in Karlstad brings a gentle transition from the warmth of summer to the crispness of autumn. With a maximum temperature that tends to hover around a comfortable level, the days still hold on to some warmth, but the average temperature signals a shift in the season. The month sees a notable increase in precipitation, with regular rain showers contributing to the lush landscape. Humidity remains high, adding a certain coolness to the air, making it feel refreshing yet damp. As the weather patterns change, September stands out as a month of contrast and preparation for the cooler days ahead. For a deeper insight into its unique climate, visit Karlstad Climate.