September Weather in Vianden, Luxembourg

Last updated: August 21, 2025

September in Vianden, Luxembourg offers a captivating blend of warm sunshine and refreshing autumn breezes. With maximum temperatures reaching a sizzling 32°C (90°F), the month frequently showcases the last remnants of summer. The average temperature settles around a comfortable 14°C (57°F), while chilly nights can drop to a minimum of 3°C (37°F). Visitors may encounter occasional rainfall, with a total precipitation of 63 mm (2.5 in) spread over approximately 9 days, contributing to the region’s lush greenery. With a humidity level averaging 83%, the air remains pleasantly invigorating, making September an ideal time to explore Vianden's enchanting landscapes.

September Temperature in Vianden

In September, Vianden experiences a delightful transition as summer gradually gives way to autumn. With temperatures ranging from a comfortable 3°C (37°F) at night to a pleasant 32°C (90°F) during the day, the month strikes a balance that invites both outdoor adventures and cozy evenings. The average temperature of 14°C (57°F) underscores this seasonal shift, providing a perfect backdrop for exploring the picturesque landscapes. As the warmth from summer lingers, visitors can enjoy the last vestiges of sunshine before the cooler days of October arrive, making September a charming time to immerse oneself in Vianden’s natural beauty.

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

The chart illustrates September temperature patterns in Vianden, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Vianden, 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).
JanFebMarAprMayJunJulAugSepOctNovDec343741485463646457504138
Data source: Temperature data for Vianden 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 Vianden

September in Vianden, Luxembourg, brings a moderate decline in precipitation, with 63 mm (2.5 inches) of rainfall over 9 days. This is notably less than in the preceding months, particularly the heavier summer months like August, which saw 70 mm of rain. The trend of more consistent rainfall seems to taper off as the region transitions into autumn. While September marks a shift towards drier weather, it still provides enough moisture to keep the landscape vibrant before winter's onset. Overall, the decrease in rainfall compared to the peak summer months indicates a gradual move towards the more typically damp conditions expected later in the year.

September Precipitation Trends in Vianden

The chart displays monthly precipitation patterns in Vianden, 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 Vianden, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec7273824173767770637564114
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Vianden

As summer transitions into autumn, September in Vianden, Luxembourg, experiences a slight uptick in humidity, averaging around 83%. This marks a subtle rise from the drier days of August, which boasted 80% humidity. The warmth of late summer still lingers, contributing to a more humid atmosphere, yet it's not as oppressive as earlier months like January and February, which consistently hover above 90%. Overall, September serves as a gentle bridge, where the refreshing embrace of cooler air begins to blend with the remnants of summer humidity, setting the stage for the wetter months ahead.

September Average Humidity in Vianden

This chart illustrates the average monthly humidity levels in Vianden, 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 Vianden is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec92%90%88%84%81%82%82%80%83%89%91%93%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Vianden

As summer wanes into September in Vianden, Luxembourg, the UV Index begins to show a noticeable decline, settling at a high level of 6. This marks a shift from the intense very high levels experienced in the preceding months of June and July, where the burn time was dangerously low at just 15 minutes. Now, with a burn time of 25 minutes, it's crucial to remain vigilant and take protective measures against harmful UV rays during outdoor activities. Overall, September may bring a slight reprieve from the peak summer sun, yet it's essential to stay informed about UV exposure. For detailed insights into the UV levels throughout the year, check out the Vianden UV Index.

Maximum UV Index Levels in Vianden for September

The chart shows the monthly maximum UV Index (UVI) for Vianden 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 Vianden typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec234689876421
Data source: Vianden 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 Vianden

September in Vianden, Luxembourg, shines with 311 hours of glorious sunshine, marking a delightful transition into autumn. As summer's warmth begins to wane, the month still boasts a remarkable amount of light, reflecting a gradual decline from the peak of 404 hours in July. This trend of diminishing sunshine continues into October, where the hours drop significantly to 225. However, September's sunlight still highlights the charm of this picturesque town, allowing residents and visitors alike to savor the lingering rays before winter's arrival. As the landscape transforms with fall colors, one can appreciate how even with fewer sunny days ahead, September offers a splendid finale to the summer season.

Monthly Sunshine Duration in Vianden: September Highlighted

The September sunshine duration represents the total number of hours Vianden 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.
JanFebMarAprMayJunJulAugSepOctNovDec98h188h250h347h381h401h404h378h311h225h165h104h
Data source: Vianden September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Vianden During September

As September rolls into Vianden, Luxembourg, the likelihood of enjoying sunny weather shows a promising uptick with a 38% chance of sunshine. This marks a notable increase from the summer months, where sun exposure fluctuates around 28-33%. Interestingly, September strikes a balance between the warmth of summer and the crisp onset of autumn, making it a delightful time for outdoor activities. Compared to the preceding months, the chance of sun reflects a gradual decline from the higher probabilities of early spring, yet remains significantly better than the gloomy days of winter ahead, where sunshine dips to as low as 8% in January. Thus, September stands out as a transitional month, offering a refreshing opportunity to bask in the sun before the cooler months set in.

Percentage of Sunny Days in September in Vianden

The chart illustrates the percentage of sunny days in Vianden 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 Vianden experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec8%31%42%46%30%30%33%28%38%27%17%12%
Data source: Vianden September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Vianden in September

As September unfolds in Vianden, Luxembourg, the days begin to shorten gently, offering approximately 12 hours of daylight. This transition marks a shift from the extended summer days of June, where daylight peaked at 16 hours, to the more mellow light of early autumn. Following the vibrant May and June months, which blessed the region with long, sun-drenched days, September serves as a graceful bridge to the cozy fall season. With daylight gradually dwindling towards October’s 10 hours, it invites a time for reflection and appreciation of nature’s changing hues, making early autumn an enchanting period worth savoring.

Average Daylight Hours in Vianden for September

The chart illustrates the variation in daylight duration in Vianden throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 36m10h 4m11h 55m13h 48m15h 26m16h 17m15h 50m14h 22m12h 33m10h 41m9h8h 7m
Data source: Vianden daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Vianden

As September ushers in the transition to autumn in Vianden, Luxembourg, its winds gently calm, averaging a modest 2.4 m/s (5 mph), the lowest of the year. This serene breeze reflects a notable trend, as the summer months gradually yield to cooler temperatures. Following a peak in May, when winds picked up to 4.2 m/s (9 mph), the shift towards mildness becomes apparent, with July and August also experiencing relatively soft gusts. This gentle September wind invites locals and visitors alike to savor the stunning fall foliage in a tranquil setting, perfectly complementing the picturesque charm of Vianden.

Average September Wind Speed in Vianden

The chart displays monthly wind speed patterns in Vianden, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.03.83.83.44.22.63.03.32.4 m/s3.73.03.5
Data source: Vianden September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Vianden Compares to Other Months

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

In September, the weather tends to be much warmer, with temperatures ranging from a pleasant 3°C (37°F) at night up to a high of 32°C (90°F) during the day. The average temperature is around 14°C (57°F), accompanied by relatively low precipitation of 63 mm (2.5 in) over about 9 days, and the humidity is around 83%. In contrast, January brings a stark shift to winter, with much colder temperatures ranging from a frigid -14°C (8°F) at night to a milder 11°C (52°F) during the day, resulting in an average of just 1°C (35°F). While precipitation is slightly higher at 72 mm (2.8 in) across 12 days, the humidity also increases to 91%. For more details, you can check Vianden weather in January.

September and February showcase distinct weather patterns, reflecting the transition between summer and winter. In September, temperatures can range from a refreshing 3°C (37°F) at night to a warm 32°C (90°F) during the day, with an average of 14°C (57°F). The month tends to be humid, with 83% humidity and about 63 mm (2.5 in) of precipitation over approximately 9 days. In contrast, February is much colder, with minimum temperatures dropping to -12°C (12°F) and a maximum of 18°C (65°F), averaging around 3°C (37°F). Precipitation in February is slightly higher at 73 mm (2.9 in) and occurs on about 12 days, accompanied by higher humidity at 90%. For more details on February weather, you can refer to Vianden weather in February.

September and March present distinctly different weather patterns. In September, temperatures range from a minimum of 3°C (37°F) to a maximum of 32°C (90°F), with an average of 14°C (57°F). The month experiences approximately 63 mm (2.5 in) of precipitation over about 9 days and a humidity level of 83%. In contrast, March sees colder conditions, with temperatures varying from a low of -13°C (8°F) to a high of 21°C (70°F), averaging around 5°C (42°F). Precipitation in March is slightly higher at 82 mm (3.2 in), spread across 16 days, and humidity is also elevated at 88%. The contrasting temperatures and precipitation patterns highlight the transition from the warmth of early autumn in September to the chilly beginnings of spring in March. For more details, check Vianden weather in March.

September and April exhibit distinct weather patterns that reflect the transition between summer and autumn, and winter to spring, respectively.

In September, temperatures range from a mild 3°C (37°F) at night to a warm maximum of 32°C (90°F) during the day, averaging around 14°C (57°F). The month receives more precipitation, totaling 63 mm (2.5 in) over 9 days, while humidity levels sit at 83%.

Conversely, April features cooler temperatures, with nighttime lows dipping to -3°C (26°F) and daytime highs reaching up to 26°C (78°F), averaging 9°C (48°F). It also has less precipitation, accumulating 41 mm (1.6 in) over the same number of rain days, with humidity slightly higher at 84%.

For more detailed insights, check out Vianden weather in April.

In comparing the weather of September and May, September generally experiences warmer temperatures, with averages around 14°C (57°F) and maximums reaching up to 32°C (90°F). In contrast, May starts a bit cooler, with an average of 12°C (54°F) and maximum temperatures peaking at 30°C (86°F). Both months receive a comparable amount of precipitation, but May tends to see rain over a greater number of days, totaling 14 days compared to September’s 9 days. Humidity levels in both months are quite similar, with September at 83% and May slightly lower at 81%. For more detailed insights into the weather conditions, you can check Vianden weather in May.

In comparing the weather of September and June, one can observe distinct differences and similarities. September generally experiences slightly cooler temperatures, with a minimum of 3°C (37°F) and an average of 14°C (57°F), while June starts off warmer with a minimum of 6°C (43°F) and an average of 17°C (63°F). Both months can reach a maximum of 32°C (90°F), showcasing the potential for heat during late spring and early autumn. However, September sees a decrease in precipitation days with 9 days of rain accumulating to 63 mm (2.5 in), compared to June's 13 rainy days totaling 76 mm (3.0 in). Humidity levels remain fairly consistent, with September at 83% and June at 82%. For those interested in a deeper look at June's weather specifics, visit Vianden weather in June.

September weather shows a wider temperature range compared to July, with temperatures ranging from a chilly 3°C (37°F) to a warm 32°C (90°F), resulting in an average of 14°C (57°F). In contrast, July maintains milder minimum temperatures at 6°C (44°F) and averages around 18°C (65°F), peaking at a hot 37°C (99°F). While September experiences slightly less precipitation at 63 mm (2.5 in) over 9 days, July sees more rainfall at 77 mm (3.0 in) distributed across 11 days. Both months exhibit high humidity levels, with September at 83% and July at 82%. For more details on July weather, you can check Vianden weather in July.

In comparing the weather between September and August, September showcases a wider temperature range with a minimum of 3°C (37°F) and a maximum of 32°C (90°F), allowing for cooler nights and warmer days. In contrast, August typically experiences milder temperatures, ranging from a minimum of 5°C (41°F) to a maximum of 34°C (93°F), with a warmer average of 18°C (64°F). Precipitation in September totals 63 mm (2.5 in) over 9 days, slightly less than August's 70 mm (2.7 in) spread over 14 days, indicating a generally drier September. Humidity levels are higher in September at 83%, compared to August's 80%. For more details, you can check Vianden weather in August.

In September, the weather features a broader temperature range, with minimums around 3°C (37°F) and maximums soaring up to 32°C (90°F), leading to an average of 14°C (57°F). The month also sees significant humidity at 83%, alongside 63 mm (2.5 in) of precipitation over 9 days. In contrast, October brings cooler conditions, with temperatures dipping to a minimum of 0°C (32°F) and an average of 10°C (50°F), while the maximum reaches 24°C (75°F). This month experiences slightly higher precipitation at 75 mm (3.0 in) spread over 11 days and an increase in humidity to 89%. For more detailed information, you can check Vianden weather in October.

September and November present contrasting weather patterns, reflecting the transition from the warmth of late summer to the chill of late autumn. In September, temperatures range from a pleasant minimum of 3°C (37°F) to a maximum of 32°C (90°F), with an average of 14°C (57°F). The month sees relatively lower humidity at 83% and a precipitation total of 63 mm (2.5 in) over about 9 rainy days.

In stark contrast, November experiences much cooler temperatures, with a minimum of -5°C (23°F) and an average of 5°C (41°F), peaking at 18°C (65°F). The humidity rises slightly to 91%, and the month records a similar precipitation total of 64 mm (2.5 in) across approximately 12 days. This shift in weather signifies not only a drop in temperature but also an increase in damp and chilly conditions. To learn more about what to expect, you can visit Vianden weather in November.

September and December showcase strikingly different weather patterns. In September, temperatures range from a mild 3°C (37°F) at night to a warm 32°C (90°F) during the day, with an average of 14°C (57°F). The month also experiences moderate precipitation of 63 mm (2.5 in) over about 9 days, accompanied by a humidity level of 83%. In contrast, December sees much colder temperatures, with a minimum of -5°C (23°F) and a maximum of 13°C (56°F), leading to an average temperature of just 3°C (38°F). This winter month brings heavier rainfall, totaling 114 mm (4.5 in) across 19 days, and a higher humidity of 93%. For more detailed information, you can visit Vianden weather in December.

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Conclusion: What to Expect From September Weather in Vianden

As September unfolds in Vianden, it offers a distinctive transition into autumn with a mix of warm and cool days. Unlike the sizzling summer, September’s temperatures showcase a dramatic dip, averaging around a pleasant 14°C, while the occasional highs can reach up to a sweltering 32°C. Visitors can expect more frequent rainfall, with approximately 63 mm falling over about 9 days, adding a refreshing touch to the air but also a higher humidity level of 83%. This blend of moderate warmth and increased moisture makes September a unique month, bridging the summer's heat with the crispness of fall. For those keen on understanding the nuances of Vianden’s weather throughout the year, check out Vianden Climate.