Last updated: August 21, 2025
September in Espoo, Finland presents a refreshing transition from summer to autumn, with maximum temperatures reaching a pleasant 23°C (73°F) and an average of 12°C (54°F). As the month unfolds, the temperature can dip to a chilly -1°C (31°F), reminding residents of the coming cooler days. With precipitation measuring 71 mm (2.8 in) across approximately 13 days, September brings a fair share of rain, contributing to the region's lush landscapes. The high humidity level of 90% adds a touch of moisture to the crisp autumn air, creating a unique atmosphere that is both invigorating and vibrant. This month is a perfect time to witness the changing colors of nature while enjoying the cool, refreshing breeze of early fall.
In September, temperatures in Espoo, Finland begin to hint at the approaching autumn, showcasing a notable decline from the summer's warmth. With minimums dipping to -1°C (31°F) and average highs reaching a comfortable 23°C (73°F), the month presents a delicate balance of cool and mild days. This transitional period sees an average temperature of 12°C (54°F), which reflects a gradual shift from the vibrant warmth of summer to the crispness of fall. As the leaves begin to change, September offers a blend of refreshing breezes and sunny afternoons, inviting both locals and visitors to enjoy the beauty of the season before the chill sets in.
In September, Espoo, Finland experiences a notable shift in precipitation as it transitions from late summer to early autumn. With 71 mm (2.8 in) of rain recorded over 13 days, the month reflects a slight increase in both moisture and frequency compared to the preceding months of August and July. This uptick is indicative of the changing seasons, as September's rainfall serves as a precursor to the wetter conditions that characterize the coming months. The combination of consistent rain and cooler temperatures signals nature's preparation for the crisp Finnish autumn, enhancing the lush landscapes that the region is known for during this time of year.
In September, humidity in Espoo, Finland experiences a noticeable peak at 90%, marking a transition from the warmer summer months into the cooler fall season. This month serves as a bridge, as humidity levels gradually decline from the summer's 83% in August but remain significantly elevated compared to the lower figures seen in late spring, such as May's 75%. As the year progresses, humidity tends to rise again in the chilly months ahead, with October seeing a slight increase to 93%. Overall, the trend illustrates a distinct seasonal ebb and flow, with September holding onto a degree of summer's moisture while preparing for the crisp autumn air.
In September, the UV Index in Espoo holds steady at 4, indicating a moderate exposure category. This marks a decrease from the peak summer months of July and June, where the index reached a high of 7, necessitating more cautious sun exposure with burn times reduced to just 25 minutes. As we transition into autumn, September's UV levels allow for approximately 30 minutes of safe sun exposure, striking a balance for outdoor activities. This trend reflects the broader pattern of declining UV levels as the seasons change, making it crucial to stay aware of the sun's intensity. For more detailed information, you can check the Espoo UV Index.
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As summer begins to fade, September in Espoo still offers a generous 290 hours of sunshine, reflecting the lingering warmth of the season. While this marks a noticeable dip from the sun-soaked days of July and June, it remains a substantial amount compared to the greyer months ahead. The trend throughout the year shows an upward trajectory from the chilly hours of January, where sunlight barely reaches 55 hours, soaring to peak brightness in May and June, with 451 and 493 hours respectively. In September, the days may shorten, but the sunlight still dances across the charming landscapes of Espoo, inviting residents and visitors alike to savor the last golden rays before autumn takes hold.
In Espoo, Finland, the likelihood of sunny weather in September mirrors the transitional nature of early autumn, with the sun making an appearance approximately 28% of the time. This is consistent with the trend seen in late summer, where August also offers a similar chance of sunshine. As we move from the bright days of July and June—boasting over half the days basked in sunlight—the probability begins a gradual decline, hinting at the approach of the cloudier months ahead. While September still allows for pleasant sunny spells, it serves as a gentle reminder of the shifting seasons and the cooler days to come.
In September, Espoo experiences a notable transition as daylight begins to wane, offering about 12 hours of sunlight. This marks a gradual decline from the long, sun-drenched days of summer, with 18 hours in June and 15 hours in August. As the month progresses, the vibrant hues of autumn emerge, hinting at the cooler days ahead. The rich shift in daylight serves as a gentle reminder of the changing seasons, with the promise of cozy evenings becoming more prevalent. The trend reveals a steady descent into shorter days, leading into the more subdued light of October with only 10 hours of daylight to follow. This rhythmic ebb and flow of daylight reflects nature’s cyclical beauty, inviting residents to embrace the cozy charm of fall.
In September, Espoo enjoys a gentle breeze, marked by an average wind speed of 4.1 m/s (9 mph). This slight uptick from the calm of summer months is a harbinger of autumn, reflecting a subtle shift as the season transitions. Compared to the lower speeds observed in June (3.0 m/s) and July (3.5 m/s), September strikes a balance between the tranquil winds of summer and the brisk gusts expected in October, which averages 5.2 m/s (12 mph). This trend of increasing wind speed as summer cedes to fall not only invigorates the air but also enhances the vibrant hues of the surrounding landscape, making it an ideal time for nature lovers to explore the beauty of Espoo.
Weather in Espoo varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Espoo, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present a stark contrast in weather conditions. September typically features milder temperatures, with highs averaging around 23°C (73°F) and lows hovering at 1°C (34°F), while January is much colder, with maximum temperatures only reaching 8°C (46°F) and plunging to a chilling -23°C (-8°F) at night. Precipitation is fairly comparable, with September seeing 71 mm (2.8 inches) and January slightly lower at 56 mm (2.2 inches), though both months experience a similar number of rainy days—13 in September and 12 in January. Additionally, the humidity in January is notably high at 97%, compared to 90% in September, contributing to a distinctly different atmospheric feel. For a more detailed look at January weather, visit Espoo weather in January.
September and February present contrasting weather experiences. In September, temperatures range from a chilly minimum of -1°C (31°F) to a pleasant maximum of 23°C (73°F), with an average of 12°C (54°F). The month sees about 71 mm (2.8 in) of precipitation over 13 days, accompanied by high humidity levels of 90%. Conversely, February is significantly colder, with temperatures dipping to a minimum of -21°C (-6°F) and an average of -3°C (26°F), peaking at only 6°C (43°F). The month receives less precipitation at 48 mm (1.9 in) over 10 days, but the humidity is slightly higher at 95%. For a more detailed look at February weather patterns, visit Espoo weather in February.
September and March showcase contrasting climates, with September bringing milder temperatures and a general sense of warmth. With an average temperature of 12°C (54°F) and highs reaching up to 23°C (73°F), September experiences a comfortable atmosphere despite some rainfall, averaging 71 mm over 13 rainy days and 90% humidity. In stark contrast, March is cold, with temperatures averaging -1°C (31°F) and highs only reaching 10°C (50°F). The month experiences colder conditions, with lows dipping to -22°C (-7°F) and slightly less precipitation at 53 mm over 12 days, accompanied by a humidity level of 93%. For more detailed weather information, you can view Espoo weather in March.
In comparing the weather of September to that of April, it's evident that September generally offers a milder climate. With average temperatures of 12°C (54°F) and maximums reaching up to 23°C (73°F), it is significantly warmer than April, which has an average temperature of just 4°C (39°F) and a maximum of 19°C (66°F). Additionally, September experiences more precipitation, totaling 71 mm (2.8 in) over 13 days, compared to April's 45 mm (1.8 in) over 9 days. Humidity levels remain quite high in both months, with September at 90% and April slightly lower at 86%. For more details, check out Espoo weather in April.
September and May present contrasting weather patterns, with September featuring milder temperatures and higher humidity levels. In September, the temperatures range from a minimum of -1°C (31°F) to a maximum of 23°C (73°F), with an average of 12°C (54°F) and 71 mm (2.8 in) of precipitation spread over 13 days. The humidity is notably high at 90%, contributing to a damp atmosphere. In contrast, May showcases slightly cooler temperatures, ranging from a minimum of -3°C (28°F) to a maximum of 26°C (79°F) with an average of 10°C (50°F). May also experiences less precipitation, totaling 54 mm (2.1 in) over just 10 days and a more comfortable humidity level of 75%. For those interested in more details about the weather in May, check Espoo weather in May.
In September, the weather is generally cooler with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 23°C (73°F), while the average temperature sits at around 12°C (54°F). This month experiences relatively high humidity at 90% and sees about 71 mm (2.8 in) of precipitation over 13 days. In contrast, June offers milder conditions, with temperatures ranging from a minimum of 3°C (39°F) to a maximum of 29°C (85°F) and an average of 16°C (61°F). June typically has lower humidity at 75% and less rainfall, with only 55 mm (2.2 in) expected over 9 days. For more detailed information, you can visit Espoo weather in June.
In comparing the weather between September and July, we see a noticeable shift in temperature and overall climate conditions. September experiences cooler temperatures, with a minimum of -1°C (31°F), an average of 12°C (54°F), and a maximum of 23°C (73°F). In contrast, July boasts milder temperatures ranging from a minimum of 8°C (46°F) to an average of 18°C (64°F), peaking at 31°C (88°F). Additionally, while both months see a significant amount of precipitation, July has slightly higher rainfall at 84 mm (3.3 in) over 12 days compared to September's 71 mm (2.8 in) over 13 days. The humidity levels also differ, with September presenting a much higher average humidity at 90% compared to July's 80%. For more details on July's weather, you can check Espoo weather in July.
In comparing the weather of September to that of August, we notice a significant drop in temperatures. September registers a minimum temperature of -1°C (31°F) and an average of 12°C (54°F), while August enjoys milder temperatures with a minimum of 7°C (45°F) and an average of 16°C (62°F). The maximum temperatures also reflect this shift, with September peaking at 23°C (73°F) compared to August's 28°C (83°F). Precipitation levels are somewhat similar, with September recording 71 mm (2.8 in) over 13 days and August slightly higher at 77 mm (3.0 in) over 12 days. Notably, September experiences increased humidity at 90%, compared to August's 83%. For more detailed insights about August, you can visit Espoo weather in August.
In September, the weather features a mild average temperature of 12°C (54°F), with highs reaching up to 23°C (73°F) and lows dropping to -1°C (31°F). The month sees about 71 mm (2.8 in) of precipitation over 13 days, with a relatively high humidity level of 90%. In contrast, October brings cooler conditions, with an average temperature of 7°C (45°F) and maximum temperatures only reaching 16°C (62°F). Precipitation increases to 88 mm (3.5 in) spread over 16 days, while humidity rises slightly to 93%. For more detailed weather information for October, you can visit Espoo weather in October.
In September, the weather in Espoo typically features milder temperatures ranging from a minimum of -1°C (31°F) to a maximum of 23°C (73°F), with an average of 12°C (54°F). The month experiences significant rainfall, totaling 71 mm (2.8 in) across about 13 days, and the humidity hovers around 90%. In contrast, November brings cooler temperatures, with a minimum of -7°C (19°F) and a maximum of 12°C (54°F), resulting in an average of just 3°C (38°F). The precipitation slightly decreases to 63 mm (2.5 in) over roughly the same number of days, while humidity rises to 94%. For a more detailed look at the weather in November, you can visit Espoo weather in November.
In September, the weather tends to be milder, with average temperatures ranging from a minimum of -1°C (31°F) to a maximum of 23°C (73°F). During this month, precipitation totals around 71 mm (2.8 in), occurring over approximately 13 days, and humidity levels are relatively high at 90%. In contrast, December brings a significant chill, with average temperatures dropping to a minimum of -17°C (1°F) and a maximum of only 7°C (44°F). The month experiences slightly more precipitation at 74 mm (2.9 in) across about 15 days, paired with even higher humidity at 95%. For more detailed information, check Espoo weather in December.
As September rolls into Espoo, the weather begins to shift, offering a distinct transition from the warmth of summer to the chill of autumn. Temperatures typically peak at a comfortable 23°C (73°F), but the average settles around a cooler 12°C (54°F), with occasional dips to frosty lows, reminding residents that winter is on the horizon. This month also sees a notable increase in precipitation, with about 71 mm (2.8 in) of rainfall over approximately 13 days, creating a lush, green landscape but also contributing to a humidity level hovering near 90%. Together, these factors create a unique weather profile in September, contrasting sharply with the drier, sunnier conditions of July and August. For more detailed insights on seasonal shifts, explore the comprehensive weather patterns at Espoo Climate.