September Weather in Haemeenlinna, Finland

Last updated: August 21, 2025

September weather in Haemeenlinna, Finland brings a captivating transition as summer bids farewell. With daily maximum temperatures reaching up to 23°C (74°F), and an average of around 11°C (52°F), the crispness of autumn begins to emerge. Nights can be quite chilly, dipping to a minimum of -2°C (29°F), reminding residents of the forthcoming seasonal shift. Rainfall is relatively frequent, with 65 mm (2.6 in) over 13 days, contributing to a lush landscape accompanied by a high humidity level of 90%. This combination of moderate warmth and moisture sets the stage for stunning fall foliage, making September a picturesque time to experience Haemeenlinna's natural beauty.

September Temperature in Haemeenlinna

As September unfolds in Hämeenlinna, Finland, the temperatures begin to shift, heralding the transition from summer warmth to autumn chill. The month starts with a refreshing minimum of -2°C (29°F), while the average temperature hovers around a comfortable 11°C (52°F), making it an ideal time for outdoor activities. Daytime highs can reach up to 23°C (74°F), inviting residents and visitors alike to enjoy the lingering warmth before winter beckons. This distinct change signals the gradual arrival of cooler days, setting the stage for the crisp, colorful beauty of autumn that follows.

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

The chart illustrates September temperature patterns in Haemeenlinna, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Haemeenlinna, 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).
JanFebMarAprMayJunJulAugSepOctNovDec252429385061636052433628
Data source: Temperature data for Haemeenlinna generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Haemeenlinna

September in Hämeenlinna, Finland, marks a shift toward the wetter days of autumn, with precipitation reaching 65 mm (2.6 in) over the month. This robust rainfall is accompanied by 13 days of precipitation, closely aligning with the trend seen in August. While the amount slightly decreases from the summer high of July's 85 mm (3.4 in), it reflects a steady pattern of increasing wetness as the year progresses. The transition into fall highlights a growing propensity for rain, indicative of the changing seasons, and sets the stage for the approaching chill of October, which typically sees an increase to 75 mm (2.9 in).

September Precipitation Trends in Haemeenlinna

The chart displays monthly precipitation patterns in Haemeenlinna, 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 Haemeenlinna, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec484143466071858065755263
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Haemeenlinna

In September, Haemeenlinna experiences a notable increase in humidity, soaring to 90% after the relatively lower levels of the summer months. This rise signals the transition from the warmth of summer, where humidity levels hovered around 80-83%, to the cooler and more variable autumn conditions. Although still humid, September's levels are a slight dip from January's peak at an impressive 97%, highlighting a seasonal shift as the region prepares for the winter months ahead. This gradual change in humidity is reflective of Finland's unique climate patterns, where the crispness of autumn brings about a refreshing yet damp atmosphere, paving the way for the chilly embrace of October and beyond.

September Average Humidity in Haemeenlinna

This chart illustrates the average monthly humidity levels in Haemeenlinna, 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 Haemeenlinna is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec97%95%93%87%75%75%80%83%90%93%94%95%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Haemeenlinna

As September rolls into Haemeenlinna, Finland, the UV Index dips to a moderate level of 3, indicating a slight decrease from the summer highs experienced in June and July. With a burn time of approximately 30 minutes, it’s a signal that while the sun is still shining, precautions are advisable. This month mirrors the trends seen in March, where conditions also hover around a moderate UV Index. As we transition into autumn, this reduction not only marks a shift in how residents should plan their outdoor activities but also reflects the gradual waning of the intense summer sunshine. For more details on UV levels throughout the year, visit Haemeenlinna UV Index.

Maximum UV Index Levels in Haemeenlinna for September

The chart shows the monthly maximum UV Index (UVI) for Haemeenlinna 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 Haemeenlinna typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec113456653211
Data source: Haemeenlinna 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 Haemeenlinna

September in Hämeenlinna, Finland, marks a gentle transition from the vibrant summer months into the gradual descent of autumn. With 267 hours of sunshine, September still offers a substantial glimpse of light, albeit significantly less than the peak sunlight of June with 479 hours. As the days begin to shorten, there's a noticeable dip from the 388 hours enjoyed in August, yet it remains brighter than the dimmer months ahead. This balance allows for the last vibrant hues of summer to linger, making September a beautiful time to appreciate the warm days before the winter chill sets in, inviting both residents and visitors to relish the outdoors amidst the fading sunlight.

Monthly Sunshine Duration in Haemeenlinna: September Highlighted

The September sunshine duration represents the total number of hours Haemeenlinna 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.
JanFebMarAprMayJunJulAugSepOctNovDec44h138h249h346h431h479h467h388h267h158h88h41h
Data source: Haemeenlinna September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Haemeenlinna During September

As September rolls into Haemeenlinna, the likelihood of sunny weather starts to dip slightly, with only a 25% chance of sunshine. This marks a transition from the more generous sunny days of summer, where July peaks at 54% and June follows closely at 50%. The emerging autumn chill begins to overshadow the remnants of warmth, leading to fewer bright days compared to the peak months of May and June. However, September still retains a moderate likelihood of pleasant weather, making it a charming time to enjoy the early autumn hues before the colder months take hold.

Percentage of Sunny Days in September in Haemeenlinna

The chart illustrates the percentage of sunny days in Haemeenlinna 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 Haemeenlinna experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec3%14%37%42%30%50%54%24%25%13%15%11%
Data source: Haemeenlinna September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Haemeenlinna in September

As September rolls into Hämeenlinna, Finland, the daylight hours begin to wane, offering a gentle transition from the long, sun-drenched days of summer. With approximately 12 hours of daylight, the month acts as a bridge between the bright summer months and the shorter days that follow in October. This gradual decrease from August's 15 hours of light illustrates the shifting seasons, where nature prepares for the cozy embrace of autumn. The daylight trend reveals not only a reduction in sunlight but also an opportunity to enjoy the rich colors of fall, making September a picturesque time to experience the charm of Hämeenlinna.

Average Daylight Hours in Haemeenlinna for September

The chart illustrates the variation in daylight duration in Haemeenlinna throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec6h 32m9h 1m11h 51m14h 44m17h 27m19h 4m18h 11m15h 39m12h 49m9h 58m7h 16m5h 40m
Data source: Haemeenlinna daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Haemeenlinna

As September settles in Hämeenlinna, the air is energized with a gentle breeze, reflecting an average wind speed of 3.3 m/s (7 mph). This slight increase from the summer's milder winds marks a transition into the brisker months ahead. Interestingly, while summer was marked by more subdued breezes, September's winds still maintain a comfortable consistency, aligning closely with the previous months' patterns. Just a month prior, August recorded a slightly higher average at 3.5 m/s (8 mph), but the shift to autumn heralds a gradual uptick as October approaches, promising an even sharper breeze at 4.2 m/s (9 mph). This subtle shift showcases Hämeenlinna’s dynamic weather patterns, where each month brings its own unique rhythm, inviting both residents and visitors to embrace the changing seasons.

Average September Wind Speed in Haemeenlinna

The chart displays monthly wind speed patterns in Haemeenlinna, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.13.03.93.43.12.72.93.53.3 m/s4.23.53.4
Data source: Haemeenlinna September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Haemeenlinna Compares to Other Months

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

September and January present stark contrasts in weather. In September, temperatures range from a chilly -2°C (29°F) at night to a pleasant 23°C (74°F) during the day, with an average of 11°C (52°F) and 65 mm (2.6 in) of rain across 13 days, coupled with a humidity level of 90%. In contrast, January experiences much harsher conditions, with nighttime lows plunging to -25°C (-13°F) and daytime highs only reaching 8°C (46°F), averaging at -4°C (25°F). Despite having less rainfall at 48 mm (1.9 in) over 11 days, the humidity in January rises to a significant 97%. For more details on January weather, check out Haemeenlinna weather in January.

September and February exhibit stark contrasts in weather patterns. September typically experiences milder temperatures, with averages around 11°C (52°F) and a maximum of 23°C (74°F), while February is much colder, featuring a brisk average of -5°C (24°F) and peaks at only 7°C (44°F). Precipitation is more frequent in September, with 65 mm (2.6 in) over 13 days, compared to February’s 41 mm (1.6 in) across 9 days. Additionally, the humidity remains high in both months, peaking at 90% in September and slightly rising to 95% in February, creating a damp chill. For those interested in more detailed insights, here's a link to explore Haemeenlinna weather in February.

In comparing the weather between September and March, it's evident that both months exhibit chilly temperatures, but with significant differences. September typically experiences milder conditions, with average temperatures around 11°C (52°F) and a maximum reaching 23°C (74°F). In contrast, March is notably colder, with average temperatures around -2°C (29°F) and a maximum only reaching 11°C (52°F), while occasionally dipping as low as -25°C (-13°F). Precipitation is also more prominent in September, totaling 65 mm (2.6 in) over 13 days, whereas March sees less rainfall at 43 mm (1.7 in) across 11 days. Additionally, humidity remains high in both months, peaking at 90% in September and slightly higher at 93% in March. For a more detailed look at March weather, visit Haemeenlinna weather in March.

In comparing the weather between September and April, notable contrasts emerge. September tends to be milder, with average temperatures around 11°C (52°F) and maximums reaching up to 23°C (74°F), while April is chillier, averaging only 3°C (38°F) and experiencing minimum temperatures that can dip as low as -13°C (9°F). Precipitation is slightly more pronounced in September, with 65 mm (2.6 in) over 13 days, compared to April's 46 mm (1.8 in) over 12 days. Humidity levels are also relatively high in both months, with September at 90% and April at 86%. For a closer look at April weather, you can check Haemeenlinna weather in April.

In September, the weather exhibits a broader temperature range, with a minimum of -2°C (29°F) and a maximum of 23°C (74°F), compared to May, which sees temperatures ranging from -4°C (26°F) to a warmer 28°C (82°F). While September experiences slightly more precipitation at 65 mm (2.6 in) over 13 days, May has a comparable amount of rainfall at 60 mm (2.4 in) over just 10 days. Additionally, September's humidity is notably higher at 90%, while May maintains a more comfortable level at 75%. Overall, September tends to be milder and wetter, whereas May often showcases warmer temperatures and more pleasant conditions. For more details on the weather, you can check Haemeenlinna weather in May.

September and June exhibit notable differences in weather patterns. In September, temperatures can drop to a minimum of -2°C (29°F), with an average of 11°C (52°F) and a maximum of 23°C (74°F). The month experiences significant humidity at 90% and approximately 65 mm (2.6 in) of precipitation over 13 days. In contrast, June showcases a warmer climate, with temperatures ranging from a minimum of 2°C (35°F) to an average of 16°C (61°F) and reaching a maximum of 31°C (88°F). June has slightly higher precipitation at 71 mm (2.8 in) over just 10 days and a lower humidity level of 75%. For more details about the weather in June, you can check Haemeenlinna weather in June.

In comparing the weather of September and July, September presents a cooler climate with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 23°C (74°F), while July boasts warmer temperatures, showing a minimum of 6°C (44°F) and reaching up to 31°C (88°F). Additionally, September experiences higher humidity levels at 90%, contributing to a chillier feel, contrasting with July's relatively lower humidity of 80%. Precipitation is also notable, with September receiving 65 mm (2.6 in) over 13 days, compared to July's 85 mm (3.4 in) across 11 days. For more detailed insights on July weather, you can visit Haemeenlinna weather in July.

In comparing the weather of September and August, September experiences cooler temperatures with a minimum of -2°C (29°F) and a maximum of 23°C (74°F), while August sees warmer conditions with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 30°C (86°F). August also has a higher average temperature of 16°C (61°F) compared to September's 11°C (52°F). Precipitation is relatively high in both months, with August receiving 80 mm (3.2 in) and September experiencing slightly less at 65 mm (2.6 in), yet both months have 13 days of rainfall. Humidity levels are higher in September at 90%, compared to August’s 83%. For more details on weather patterns, you can check Haemeenlinna weather in August.

In September, temperatures range from a chilly -2°C (29°F) at night to a comfortable high of 23°C (74°F) during the day, with an average of 11°C (52°F). The month sees about 65 mm (2.6 in) of precipitation over approximately 13 days, accompanied by a high humidity level of 90%. As October arrives, the weather becomes noticeably cooler, bringing minimum temperatures down to -6°C (22°F) and an average of 6°C (43°F), with daytime highs reaching only 18°C (65°F). Precipitation increases slightly to 75 mm (2.9 in) over 15 days, with humidity also rising to 93%. For further details on October weather patterns, you can visit Haemeenlinna weather in October.

In September, the weather typically features milder temperatures, with a minimum of -2°C (29°F) and an average of 11°C (52°F), peaking at a comfortable 23°C (74°F). The month experiences approximately 65 mm (2.6 in) of precipitation across 13 days, with humidity levels at 90%. In contrast, November ushers in much colder conditions, with temperatures dropping significantly: a minimum of -11°C (13°F), an average of 2°C (36°F), and a maximum of 12°C (54°F). Precipitation is slightly lower at 52 mm (2.1 in) over 11 days, yet the humidity rises to 94%, adding to the chill. For a closer look at November conditions, you can check Haemeenlinna weather in November.

September offers a milder climate with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 23°C (74°F), making it a season of transition as summer gives way to fall. In contrast, December brings colder conditions, with temperatures plummeting from a minimum of -20°C (-5°F) to a maximum of just 5°C (42°F), as winter settles in. While both months experience similar levels of precipitation (around 63-65 mm), December sees slightly more rainy days, totaling 14 compared to September's 13. The humidity also rises in December to 95%, compared to September's 90%, contributing to the crisp, cold air typical of winter. For more detailed insights, you can check Haemeenlinna weather in December.

Compare Haemeenlinna's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Haemeenlinna

As September unfolds in Hämeenlinna, the city's weather marks a notable transition from the warmth of summer to the crispness of fall. With temperatures averaging around 11°C (52°F), this month offers a refreshing change, showcasing warm afternoons that contrast sharply with cooler, brisk evenings. The increased humidity at 90% and rainfall over about half the month contributes to a lush, vibrant landscape, setting a picturesque scene for autumn. Though the temperatures occasionally dip to chilly lows near -2°C (29°F), the days still host a pleasant warmth that invites exploration of the stunning surroundings. For a broader look at what to expect throughout the year, check out the detailed insights provided in Haemeenlinna Climate.