September Weather in Rauma, Finland

Last updated: August 21, 2025

September in Rauma, Finland offers a delightful blend of seasonal transitions, with maximum temperatures reaching up to 22°C (71°F) and an average of 13°C (55°F). As autumn sets in, early mornings can be notably crisp, dipping to a minimum of 5°C (41°F). The month is characterized by frequent rain, accumulating about 81 mm (3.2 in) over 13 days, contributing to a muggy humidity level of 86%. This mix of warmth and moisture creates a vibrant atmosphere as the landscape begins to change, making September a fascinating time to experience Rauma's natural beauty.

September Temperature in Rauma

In September, Rauma, Finland, experiences a gentle transition from the warmth of summer to the cooler embrace of autumn. With temperatures ranging from a minimum of 5°C (41°F) to a comfortable maximum of 22°C (71°F), the month presents a delightful average of 13°C (55°F). This period marks one of the last opportunities to enjoy pleasant outdoor activities, as the days are still relatively warm and inviting. As September unfolds, residents and visitors alike can savor the vibrant autumn hues beginning to surface, creating a picturesque backdrop against the gradually cooling temperatures. This month truly encapsulates a serene shift, inviting reflection and appreciation of nature's changing palette.

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

The chart illustrates September temperature patterns in Rauma, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Rauma, 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).
JanFebMarAprMayJunJulAugSepOctNovDec312832384657626255464034
Data source: Temperature data for Rauma 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 Rauma

September in Rauma, Finland, marks a transition into the wetter autumn months, with precipitation totaling 81 mm (3.2 in) spread across 13 days. This slightly decreases from the preceding months of August, which boasted 83 mm (3.3 in), and highlights a trend of increasing rainfall as the year progresses. The shift from summer dryness to a more consistently soggy atmosphere is evident, particularly as October follows with an even heftier 101 mm (4.0 in) of precipitation over 17 days. This trend suggests that September serves as a pivotal month, bridging the gap between the warmer, drier summer and the wetter, chillier days ahead, setting the stage for an autumn characterized by significant rainfall and frequent downpours.

September Precipitation Trends in Rauma

The chart displays monthly precipitation patterns in Rauma, 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 Rauma, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec4642433639427783811017376
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Rauma

In September, Rauma, Finland, experiences a notable shift in humidity, with levels reaching 86%. This increase follows a steady decline from the peak of 92% humidity in January to 79% in August, signaling the transition from the drier summer months back to the more humid conditions typical of the autumn season. As September unfolds, humidity levels begin to rise again, aligning with the onset of cooler temperatures in October and November, where humidity stabilizes around the 90% mark. This cyclical pattern highlights Rauma's characteristic blend of moisture-laden air, especially as the long, dark winters approach, creating a unique atmospheric feel in this coastal Finnish town.

September Average Humidity in Rauma

This chart illustrates the average monthly humidity levels in Rauma, 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 Rauma is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec92%90%89%85%77%78%78%79%86%90%91%89%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Rauma

As September arrives in Rauma, Finland, the UV Index dips to a moderate level of 3, reflecting the transition into autumn. With a burn time of 30 minutes, it's a reminder that while the summer sun begins to wane, protection against UV rays remains essential. This month marks a decline from the peak summer indices, where July showcased a high UV Index of 6. Interestingly, September echoes the mild conditions of earlier spring months, such as March and April, which also featured moderate UV protection needs. As you enjoy the changing colors of the season, don’t forget to stay aware of the UV levels. For more comprehensive information, check out the Rauma UV Index.

Maximum UV Index Levels in Rauma for September

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

September in Rauma, Finland, offers a delightful transition into autumn with 301 hours of sunshine, marking a notable change from the vibrant summer months. As the sun gradually retreats, this month still provides a substantial amount of light compared to the preceding months, ensuring that the golden hues of early fall can be savored. Following the peak of 495 hours in June and 492 hours in July, September feels like a gift as daylight begins to diminish, yet it remains a brighter conclusion to the summer season than the stark 198 hours of October. This trend highlights Rauma's enchanting ability to blend the warmth of summer sunshine with the crispness of early autumn, inviting locals and visitors alike to bask in the last glow before winter sets in.

Monthly Sunshine Duration in Rauma: September Highlighted

The September sunshine duration represents the total number of hours Rauma 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.
JanFebMarAprMayJunJulAugSepOctNovDec56h158h266h359h453h495h492h421h301h198h111h64h
Data source: Rauma September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Rauma During September

In Rauma, Finland, September marks a notable shift in the likelihood of sunny weather as summer yields to the crispness of autumn. While the chances of sunshine dip to 31%—down from a more robust 62% in July and 54% in June—this still offers a pleasant opportunity for those looking to enjoy the mild early fall days. Following the sunny highs of summer, September serves as a gentle transition, with a sun-kissed memory lingering while darker days begin to loom. Despite the decline, the chance of clear skies remains significantly higher than the frigid winter months, where sunshine often plummets to a mere 7% in January. Thus, September retains a charm, inviting outdoor enthusiasts to soak in the mellow warmth before the chill of autumn fully sets in.

Percentage of Sunny Days in September in Rauma

The chart illustrates the percentage of sunny days in Rauma 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 Rauma experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec8%23%40%52%36%54%62%35%31%18%24%18%
Data source: Rauma September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Rauma in September

As September rolls into Rauma, Finland, the days begin to noticeably shorten, offering approximately 12 hours of daylight. This marks a gentle transition from the lush long summer days, where daylight peaked at an impressive 19 hours in June. The gradual decrease in sunlight through the months reflects the shift towards autumn, moving from 17 hours in May to 15 in August and down to September's values. While the allure of longer days fades, the crispness of early fall invites a new rhythm of life, as the lingering light of September still offers ample opportunities to enjoy the vibrant scenery before the days shrink further into the depths of winter.

Average Daylight Hours in Rauma for September

The chart illustrates the variation in daylight duration in Rauma throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec6h 30m9h11h 51m14h 45m17h 29m19h 8m18h 14m15h 40m12h 49m9h 57m7h 14m5h 37m
Data source: Rauma daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Rauma

As September unfolds in Rauma, Finland, the gentle breeze sees a slight dip in average wind speed, settling at 5.4 m/s (12 mph). This marks a subtle shift from the more robust gusts of late summer, where August boasted 5.5 m/s. Following the peak winds of spring, which saw 6.7 m/s in March, the transition into autumn brings a calming effect. However, the winds will soon pick up momentum, as October anticipates a brisk 7.6 m/s (17 mph), signaling that Rauma's weather is gearing up for the rich, gusty days of fall. The overall trend showcases a seasonal ebb and flow of the winds, offering a perfect backdrop for leisurely strolls along the coast, as nature prepares for the cooler months ahead.

Average September Wind Speed in Rauma

The chart displays monthly wind speed patterns in Rauma, 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.85.66.75.74.94.64.75.55.4 m/s7.66.46.5
Data source: Rauma September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Rauma Compares to Other Months

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

In September, temperatures begin to shift from the warmth of summer, with average highs around 22°C (71°F) and lows dipping to 5°C (41°F). The month experiences relatively high humidity at 86%, along with 81 mm (3.2 in) of rain over 13 days. By contrast, January brings a stark change, as temperatures plummet to a minimum of -15°C (5°F) and only reaching a maximum of 6°C (44°F), resulting in an average of -1°C (31°F). The month sees less precipitation, totaling 46 mm (1.8 in) across 11 days, but the humidity remains high at 92%. For a closer look at winter conditions, you can check out Rauma weather in January.

In September, the weather is generally mild, with temperatures ranging from a minimum of 5°C (41°F) to an average of 13°C (55°F) and reaching a maximum of 22°C (71°F). This month also sees a fair amount of rainfall, accumulating 81 mm (3.2 in) across approximately 13 rainy days, accompanied by high humidity levels of 86%. In contrast, February is much colder, with temperatures dipping to a minimum of -15°C (5°F) and averaging -2°C (28°F), peaking at only 6°C (43°F). Precipitation is lighter, totaling 42 mm (1.7 in) over 9 days, while humidity remains high at 90%. For more details on weather during this winter month, visit Rauma weather in February.

The weather in September is markedly milder than in March, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 22°C (71°F), averaging around 13°C (55°F). In contrast, March experiences much colder conditions, with temperatures dipping as low as -17°C (1°F) and only reaching a maximum of 7°C (46°F), averaging around 0°C (32°F). September also sees more precipitation, totaling 81 mm (3.2 in) across 13 days, while March has lesser precipitation of 43 mm (1.7 in) over 10 days. Despite the differences in temperature and precipitation, both months maintain high humidity levels, with September at 86% and March slightly higher at 89%. For more details on the weather during March, visit Rauma weather in March.

September and April present contrasting weather as they transition between seasons. In September, temperatures range from a minimum of 5°C (41°F) to a maximum of 22°C (71°F) with an average of 13°C (55°F), making it a generally milder month. This period also sees more rainfall, with an average precipitation of 81 mm (3.2 in) over 13 days, coupled with a higher humidity level of 86%. In comparison, April's temperatures are cooler, with a minimum of -3°C (26°F) and a maximum of 16°C (61°F), averaging around 3°C (38°F). Furthermore, April experiences significantly less precipitation, totaling 36 mm (1.4 in) across just 7 days, while maintaining a humidity level of 85%. For a closer look at April's weather specifics, you can visit Rauma weather in April.

In September, temperatures are generally milder, ranging from a minimum of 5°C (41°F) to a comfortable maximum of 22°C (71°F), with an average of 13°C (55°F). This month typically experiences 81 mm (3.2 in) of precipitation over about 13 days, coupled with a higher humidity level of 86%. In contrast, May marks the onset of warmer weather, featuring temperatures that range from a minimum of 0°C (32°F) to a maximum of 19°C (66°F), with an average of 8°C (46°F). The precipitation is significantly lower at 39 mm (1.5 in) across just 7 days, and the humidity levels are relatively lower at 77%. Overall, September boasts warmer days and higher humidity compared to the cooler, drier conditions in May. For more detailed information about May weather, you can visit Rauma weather in May.

When comparing the weather in September and June, a few key differences emerge. In June, temperatures generally range from a minimum of 6°C (42°F) to a maximum of 25°C (78°F), with an average of 14°C (57°F). September, on the other hand, sees slightly cooler temperatures, with a minimum of 5°C (41°F) and a maximum of 22°C (71°F), averaging 13°C (55°F). Additionally, June experiences less precipitation, totaling 42 mm (1.7 in) over about 7 days, compared to September's higher rainfall of 81 mm (3.2 in) spread across approximately 13 days. Humidity levels are also higher in September at 86%, compared to June’s 78%. For more details, you can check Rauma weather in June.

In comparing the weather of September and July, notable differences emerge. September experiences cooler temperatures, with a minimum of 5°C (41°F) and an average of 13°C (55°F), while July boasts warmer conditions, with temperatures ranging from a minimum of 10°C (51°F) to an average of 17°C (63°F). The maximum temperature in September reaches 22°C (71°F), compared to July's higher peak of 26°C (79°F). Additionally, September sees more precipitation, totaling 81 mm (3.2 in) over 13 days, compared to July's 77 mm (3.0 in) over 10 days. Humidity levels are also higher in September at 86%, compared to 78% in July. For more insights on July weather, you can refer to Rauma weather in July.

In comparing the weather of September and August, September tends to be cooler overall, with average temperatures ranging from a minimum of 5°C (41°F) to a maximum of 22°C (71°F), compared to August's milder range of 10°C (49°F) to 25°C (77°F). While both months experience similar levels of precipitation, with September at 81 mm (3.2 in) over 13 days and August slightly higher at 83 mm (3.3 in) over 14 days, September is notably more humid at 86% compared to August's 79%. This increased humidity in September, combined with cooler temperatures, contributes to a distinctly more brisk and overcast atmosphere. For a more detailed look at August weather, you can visit Rauma weather in August.

In September, the weather is generally milder, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 22°C (71°F) and an average of 13°C (55°F). The month sees substantial precipitation of 81 mm (3.2 in) over about 13 days, contributing to an average humidity level of 86%. In contrast, October brings a notable drop in temperatures, with minimums dropping to -1°C (31°F) and a maximum of 15°C (60°F), averaging around 8°C (47°F). Precipitation increases to 101 mm (4.0 in) across 17 days, along with a slight rise in humidity to 90%. For more detailed information on October weather, visit Rauma weather in October.

September and November present a striking contrast in weather patterns. In September, the temperatures range from a minimum of 5°C (41°F) to a pleasant average of 13°C (55°F) and can reach a comfortable maximum of 22°C (71°F). The month experiences relatively high humidity at 86% and receives about 81 mm (3.2 in) of precipitation over 13 days. In contrast, November is significantly cooler, with temperatures dipping to a minimum of -6°C (22°F) and an average of just 5°C (41°F), peaking at 12°C (54°F). While November has slightly less precipitation at 73 mm (2.9 in) over 14 days, the humidity rises to 91%, creating a noticeably chillier atmosphere. For more detailed information, you can explore Rauma weather in November.

September and December in Rauma exhibit striking contrasts in weather patterns. September experiences milder temperatures, with averages around 13°C (55°F) and highs reaching up to 22°C (71°F), while rainfall occurs over 13 days, totaling 81 mm (3.2 in). In contrast, December brings frigid temperatures, with averages plummeting to 1°C (34°F) and maximums only reaching 6°C (44°F). Precipitation in December is slightly lower at 76 mm (3.0 in), but it occurs more frequently, spanning over 16 days, with humidity levels slightly higher at 89%. For more details, visit Rauma weather in December.

Compare Rauma's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Rauma

As September rolls in, Rauma experiences a notable shift in weather, with cooler temperatures and increasing rainfall setting the tone for the autumn. Unlike the warmer summer months, this transition brings a refreshing average of 13°C (55°F), paired with higher humidity levels that often reach 86%. Rainfall becomes more frequent, with about 13 days of precipitation throughout the month, making the landscape lush but also requiring a robust umbrella. This blend of moderate warmth and persistent showers creates a unique atmosphere, perfect for cozying up with a book or exploring the town’s rich history and culture. To dive deeper into what you can expect throughout the year, visit Rauma Climate.