Last updated: August 21, 2025
In Vaasa, Finland during September, temperatures exhibit a striking range, with maximums reaching 24°C (75°F) while averaging around 11°C (52°F). As the month progresses, nighttime can bring brisk conditions, occasionally dipping to a chilly 0°C (32°F). The city sees about 75 mm (2.9 in) of precipitation spread over 13 days, contributing to an overall humidity level of 88%. This blend of cool temperatures and frequent showers creates a distinctly fresh atmosphere, characteristic of early autumn in the region.
In Vaasa, Finland, September marks a transition into cooler weather, with temperatures ranging from a minimum of 0°C (32°F) to a pleasant average of 11°C (52°F). As the month progresses, the maximum daytime highs can reach up to 24°C (75°F), providing a last taste of summer warmth before autumn sets in. This month stands out as a moderate reprieve from the extreme cold of the winter months, which can plunge as low as -25°C in January and February. The gradual decline in temperature from August's lingering warmth highlights a notable shift, setting the stage for the brisk, vibrant landscapes typical of fall in Finland. As the leaves begin to change, September offers a charming blend of mild days and refreshing evenings, making it an ideal time for outdoor exploration in this picturesque region.
September in Vaasa, Finland, marks a notable transition in precipitation patterns, with 75 mm (2.9 in) of rain falling over 13 days. This amount reflects a slight decrease from the preceding month's 84 mm (3.3 in) but remains consistent with the trend of increasing rainfall during late summer. As the season shifts, the frequency of rainy days ramps up, continuing the pattern seen in August. This shift hints at the impending autumn, where October will bring similar precipitation levels, suggesting that Vaasa prepares for a wetter season ahead. Overall, September serves as a reminder of the changing climate, reminding residents of nature's inevitable embrace as summer gives way to fall.
In Vaasa, Finland, September marks a notable shift in humidity levels, balancing the summer's drier atmosphere with an increase to 88%. This rise follows the warmer months of July and August, where humidity hovered around the low 80s, reflecting the gradual transition into autumn. As the year unfolds, humidity levels begin their ascent again, with October and November maintaining a higher range of 92%. Overall, while winter months like January and February experience the highest humidity, September serves as a pivotal point, blending summer's warmth with the impending chill of fall, inviting a refreshing yet cozy ambiance.
As summer transitions to autumn in Vaasa, Finland, September brings a moderate UV Index of 3, signaling a continued need for sun protection, with a burn time of about 30 minutes. This slight dip from the peak summer values reflects a gradual reduction in sunlight intensity, echoing the trends observed from the previous months. After enjoying higher levels in June and July, where UV exposure was classified as high, September serves as a reminder to be mindful of UV rays, especially during midday hours. As the days shorten and temperatures cool, it's still wise to check the forecast and stay informed about UV levels. For more details, visit Vaasa UV Index.
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September in Vaasa, Finland, offers a delightful transition from the sun-drenched summer months to the cooler autumn days. With 298 hours of sunshine, it marks a significant drop from the peak of 509 hours in June, yet still provides a vibrant canvas for outdoor activities and scenic views. This month bridges the intense brightness of summer and the fading light of fall, showcasing a remarkable trend in daylight that begins in January with just 48 hours and steadily climbs until reaching its zenith in June. As the daylight hours decrease heading into October, September remains a crucial time to relish the lingering warmth and sunshine, making it a cherished month in the Finnish calendar.
In Vaasa, Finland, the likelihood of sunny weather undergoes a noticeable shift as the year progresses. While January starts with a meager 5% chance of sunshine, this figure climbs steadily through the winter months, peaking at 55% in July, the height of summer. As autumn approaches, however, the forecast begins to dim; by September, the chance of encountering sunny weather drops to 24%. This declining trend continues into October, when sunny days become even rarer at 15%. Overall, the sunshine in September reflects a transitional phase, signaling the end of vibrant summer days and the onset of the cooler, cloudier months ahead.
As summer fades into autumn, September in Vaasa, Finland, offers a gentle transition with approximately 12 hours of daylight. This marks a noticeable reduction from the long, sun-soaked days of June, which basked in 20 hours of sunlight, and reflects the shift that begins in late summer. After enjoying a vibrant month of August with 16 hours of daylight, residents now experience shorter days that signal the approach of winter. The gradual decline continues into October, which sees daylight shrinking to 9 hours, emphasizing the fleeting nature of sunlight as the seasons change. This rhythmic ebb and flow of daylight not only shapes the landscape but also the daily lives of those who call Vaasa home, reminding them to savor each radiant moment while it lasts.
As September arrives in Vaasa, Finland, the winds are gently shifting, maintaining an average speed of 3.6 m/s (8 mph). This slight increase from the summer months hints at the onset of autumn, as the breezes start to carry a refreshing chill. In contrast to the quieter July and August winds, September's gusts provide a pleasant transition, aligning with the subtle but noticeable shifts in temperature and scenery. Looking ahead, October promises a more robust wind experience, with speeds climbing to an average of 4.8 m/s (11 mph), showcasing the dramatic changes typical of the season.
Weather in Vaasa varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Vaasa, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, temperatures in Vaasa range from a chilly 0°C (32°F) at night to a pleasant 24°C (75°F) during the day, resulting in an average temperature of 11°C (52°F). This month sees about 75 mm (2.9 in) of precipitation over 13 days, with humidity levels around 88%. In contrast, January brings much harsher conditions, with minimum temperatures plunging to -24°C (-11°F) and a maximum of only 8°C (47°F), resulting in an average temperature of -3°C (26°F). Although January experiences less precipitation at 38 mm (1.5 in) over 9 days, the humidity is slightly higher at 95%. For more details on how weather in January affects the region, visit Vaasa weather in January.
September and February present contrasting weather conditions indicative of seasonal change. In September, temperatures range from a chilly 0°C (32°F) at night to a pleasant 24°C (75°F) during the day, with an average of around 11°C (52°F). Precipitation is relatively moderate, totaling 75 mm (2.9 in) over 13 days, while humidity sits at a comfortable 88%.
In stark contrast, February experiences much colder temperatures, with nighttime lows plunging to -22°C (-8°F) and daytime highs only reaching 7°C (44°F), resulting in an average of -5°C (24°F). The month sees less rainfall, with 43 mm (1.7 in) over just 7 days, but the humidity is higher at 93%. For more details, you can check Vaasa weather in February.
September and March present starkly contrasting weather conditions. In September, temperatures range from a chilly 0°C (32°F) at night to a pleasant 24°C (75°F) during the day, with an average of 11°C (52°F). This month experiences 75 mm (2.9 in) of precipitation over approximately 13 days, coupled with high humidity at 88%. In contrast, March is characterized by much colder conditions, with temperatures dropping as low as -25°C (-13°F) and peaking at a modest 10°C (49°F), averaging around -1°C (30°F). Precipitation is lower, at 41 mm (1.6 in), occurring over 11 days, while humidity remains slightly higher at 91%. For more details on March conditions, you can check Vaasa weather in March.
In comparing the weather of September and April, we can observe notable differences. September generally boasts milder temperatures, with an average of 11°C (52°F) and maxima reaching up to 24°C (75°F), contrasted with April's chillier average of 3°C (37°F) and a maximum of 21°C (70°F). Furthermore, September experiences significantly more precipitation, totaling 75 mm (2.9 in) over 13 days, compared to April's 39 mm (1.5 in) across 7 days. Humidity levels are fairly similar, with September at 88% and April at 85%. For more details on April's climate in Vaasa, you can check Vaasa weather in April.
September tends to be milder than May, with average temperatures hovering around 11°C (52°F) compared to May's average of 8°C (47°F). While both months experience a range of temperatures, September can reach a maximum of 24°C (75°F), slightly lower than May's peak of 25°C (78°F). Precipitation is more frequent in September, occurring on about 13 days and totaling 75 mm (2.9 in), whereas May sees only 42 mm (1.6 in) over just 7 days. Additionally, September's higher humidity at 88% contrasts with May's 77%, resulting in a distinctly different feel for both months. For more detailed weather insights, check out Vaasa weather in May.
September and June present distinct weather patterns, with June generally enjoying warmer temperatures. In June, temperatures range from a minimum of 1°C (34°F) to a maximum of 29°C (85°F), with an average of 15°C (59°F) and less precipitation at 57 mm (2.2 in) over 10 days. In contrast, September features a cooler temperature range, with a minimum of 0°C (32°F) and a maximum of 24°C (75°F), averaging only 11°C (52°F). It experiences higher precipitation at 75 mm (2.9 in) over 13 days and maintains a higher humidity level of 88%. For more details on June weather in Vaasa, you can check Vaasa weather in June.
The weather in September is noticeably cooler than in July, with temperatures ranging from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), compared to July's minimum of 5°C (42°F) and maximum of 32°C (90°F). The average temperature in September is also lower at 11°C (52°F) versus 17°C (63°F) in July. Additionally, September experiences more precipitation, totaling 75 mm (2.9 in) over 13 days, compared to July's 59 mm (2.3 in) over 10 days, although July has slightly lower humidity at 80% compared to September's 88%. For a more detailed look at July's weather patterns, refer to Vaasa weather in July.
In September, temperatures decline noticeably compared to August, with minimums dropping to 0°C (32°F) and average highs reaching only 24°C (75°F), while August enjoys milder conditions with a minimum of 5°C (41°F) and highs peaking at 29°C (85°F). Precipitation levels are somewhat similar, with September recording 75 mm (2.9 in) versus August's 84 mm (3.3 in), although both months experience rainfall on 13 days. Humidity also sees a slight increase in September at 88%, compared to August's 82%, contributing to a more damp and crisp feel as autumn approaches. For a closer look at August's climate specifics, visit Vaasa weather in August.
September and October display quite a contrast in weather patterns, with temperatures steadily declining as autumn deepens. In September, the temperature ranges from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), with an average of 11°C (52°F). The month sees about 75 mm (2.9 in) of precipitation over 13 days, accompanied by a humidity level of 88%.
In stark contrast, October brings cooler conditions, with temperatures dipping lower, ranging from a minimum of -9°C (17°F) to a high of only 17°C (64°F), resulting in an average temperature of 6°C (43°F). This month experiences slightly higher precipitation at 84 mm (3.3 in) over 15 days, while humidity rises to 92%. For more detailed insights into October's conditions, you can visit Vaasa weather in October.
September and November present distinct contrasts in weather patterns. In September, temperatures range from a mild 0°C (32°F) to a pleasant max of 24°C (75°F), with an average of 11°C (52°F). The month sees about 75 mm (2.9 in) of precipitation over 13 days and maintains a relatively high humidity level of 88%. In stark contrast, November experiences much colder conditions, with minimum temperatures plummeting to -17°C (2°F) and a much lower average of 2°C (36°F). The maximum temperature reaches only 12°C (53°F), accompanied by reduced precipitation of 57 mm (2.2 in) over 10 days. Additionally, November's humidity slightly increases to 92%. For more detailed insights into November's weather, check out Vaasa weather in November.
In Vaasa, September showcases a mild transition into autumn with temperatures ranging from 0°C (32°F) at night to a pleasant 24°C (75°F) during the day. The month experiences 75 mm of precipitation over about 13 days, and humidity remains high at 88%. In stark contrast, December plunges into the depths of winter, where temperatures can drop to a frigid -24°C (-11°F) at night, with daytime highs averaging just -2°C (29°F) and maximum temperatures reaching only 6°C (43°F). December sees slightly lower precipitation at 53 mm over 14 days, accompanied by even higher humidity levels at 93%. For a more detailed look at December weather, check out Vaasa weather in December.
As September rolls into Vaasa, the weather begins to shift dramatically from the warm embrace of summer to the crispness of autumn. With an average temperature settling around 11°C, the month showcases a significant drop compared to the balmy warmth of July and August. The skies often blanket the city, bringing considerable precipitation on about half the days, resulting in the characteristic high humidity of 88%. This transition not only provides a refreshing change but also primes the landscape for the vibrant fall foliage that follows. To explore more about what to expect throughout the year, visit Vaasa Climate.