September Weather in Minami-Alps, Japan

Last updated: August 21, 2025

In September, the Minami-Alps region of Japan experiences a dynamic climatic shift, characterized by strong humidity levels averaging 86%. Temperatures fluctuate from a maximum of 31°C (89°F) to a minimum of 9°C (49°F), with an overall average settling at a mild 19°C (66°F). This month is notable for its substantial precipitation, accumulating around 240 mm (9.5 in) over 21 days, creating a lush, vibrant landscape. Visitors should prepare for a mix of warm days and frequent rain, making it a perfect time to witness the breathtaking beauty that the Minami-Alps has to offer.

September Temperature in Minami-Alps

In September, the Minami-Alps of Japan experience a gentle shift as the summer heat begins to wane. With temperature lows around 9°C (49°F) and daytime highs reaching a pleasant 31°C (89°F), this month marks a transition into autumnal comfort. The average temperature of 19°C (66°F) offers a delightful climate, conducive for outdoor activities and enjoying the vibrant fall foliage that starts to emerge. As the month progresses, the evenings cool down significantly, hinting at the colder months ahead, yet still allowing for warm, sun-kissed days that beckon visitors to explore the stunning natural beauty of the region. Overall, September serves as a bridge between the sweltering summer and the brisk autumn, encapsulating a perfect blend of warmth and refreshing coolness.

September Weather in Minami-Alps: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Minami-Alps, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Minami-Alps, 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).
JanFebMarAprMayJunJulAugSepOctNovDec323341495864717366564636
Data source: Temperature data for Minami-Alps 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 Minami-Alps

In September, Minami-Alps experiences a notable increase in precipitation, with 240 mm (9.5 in) of rainfall over 21 days. This marks a continuation of the region's wet season, following the heavy downpours of July and August, which saw 412 mm (16.2 in) and 216 mm (8.5 in) respectively. Interestingly, while September’s total is lower than July's peak, it signifies a robust transition into autumn, maintaining a high level of precipitation that supports the vibrant local ecosystems. As the region prepares for the cooler October, where an even higher precipitation total of 345 mm (13.6 in) is anticipated, the steady rainfall in September underscores a pattern of sustained moisture that nurtures the lush landscapes of the Minami-Alps.

September Precipitation Trends in Minami-Alps

The chart displays monthly precipitation patterns in Minami-Alps, 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 Minami-Alps, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec60761821771822184122162413457870
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Minami-Alps

In September, Minami-Alps experiences a notable humidity level of 86%, marking a slight decline from the peak summer months of July and August, which recorded humidity levels of 93% and 90% respectively. This transition indicates the tail end of a humid season, where humidity has soared since June's substantial 88%. As the region begins to shift towards autumn, the gradual decrease in moisture levels suggests a return to more moderate conditions, aligning with the trend of October's forecasted 83% humidity. This rhythmic ebb and flow of humidity throughout the year paints a vivid picture of Minami-Alps' seasonal climate, where late summer's warmth gives way to the refreshing coolness of fall.

September Average Humidity in Minami-Alps

This chart illustrates the average monthly humidity levels in Minami-Alps, 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 Minami-Alps is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%74%70%74%82%88%93%90%86%83%80%78%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Minami-Alps

As September rolls into Minami-Alps, Japan, the UV Index remains notably high at 10, categorizing the exposure as very high. This marks a slight decrease from the intense summer months, where the UV levels peaked at 12 in June through August. With a burn time of just 15 minutes, it's evident that the need for sun protection is still crucial during this transitional period. The gradual decline from summer's extreme levels highlights the importance of vigilance as outdoor activities might continue well into the fall. For a comprehensive overview of UV levels throughout the year, check out Minami-Alps UV Index.

Maximum UV Index Levels in Minami-Alps for September

The chart shows the monthly maximum UV Index (UVI) for Minami-Alps 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 Minami-Alps typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec479101112121210764
Data source: Minami-Alps 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 Minami-Alps

In Minami-Alps, Japan, September enjoys a delightful balance of sunshine with 238 hours of sunlight, marking a gentle decline after the summer's peak. The month stands as a transition from the vibrant warmth of August, which boasts a generous 284 hours. Following this seasonal shift, September's rays usher in the onset of autumn, paving the way for October's softer light at 216 hours. Interestingly, this decrease from the summer peak reflects a broader trend where daylight gradually wanes from the brightness of April's 278 hours through the cooler months. As the landscape shifts to embrace autumn hues, September offers a reassuring balance of light that invites both reflection and exploration in the stunning Minami-Alps region.

Monthly Sunshine Duration in Minami-Alps: September Highlighted

The September sunshine duration represents the total number of hours Minami-Alps 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.
JanFebMarAprMayJunJulAugSepOctNovDec194h239h267h278h291h263h228h284h238h216h237h237h
Data source: Minami-Alps September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Minami-Alps During September

In September, Minami-Alps, Japan, experiences a modest 20% chance of sunny weather, reflecting a general decline in sunshine as summer transitions to autumn. This trend follows a pattern observed throughout the warmer months, where the likelihood of sunny days peaks at 61% in February but gradually diminishes, particularly in June, July, and August, which all hover around 22%. As September unfolds, the area's chance of sun is notably lower than the preceding months, hinting at the arrival of cooler and cloudier weather that persists into October. Thus, while outdoor enthusiasts may find the allure of Minami-Alps inviting in September, it's wise to prepare for a backdrop of variable skies, signaling the shift toward the cozy embrace of autumn.

Percentage of Sunny Days in September in Minami-Alps

The chart illustrates the percentage of sunny days in Minami-Alps 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 Minami-Alps experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec55%61%39%41%22%16%22%22%20%40%51%68%
Data source: Minami-Alps September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Minami-Alps in September

In Minami-Alps, Japan, September marks the transition from the long summer days to the shorter autumn light, with daylight lasting approximately 12 hours. This month sees a gradual decline from the peak of 14 hours enjoyed in June, July, and August, reflecting the subtle shift in seasons. As the days shorten, the vibrant hues of autumn begin to emerge, making September a time of stunning natural beauty. Following this month, daylight continues to dwindle, dropping to 11 hours in October and further decreasing as winter approaches. This cyclical pattern highlights the region's distinct seasonal changes, inviting residents and visitors alike to appreciate the evolving landscape throughout the year.

Average Daylight Hours in Minami-Alps for September

The chart illustrates the variation in daylight duration in Minami-Alps throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 2m10h 52m11h 58m13h 5m14h 2m14h 30m14h 16m13h 26m12h 22m11h 15m10h 16m9h 46m
Data source: Minami-Alps daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Minami-Alps

As summer gently yields to autumn, the September winds in Minami-Alps, Japan, manage to maintain a soft presence, with an average speed of 1.4 m/s (3 mph). This slight decline from the seasonal highs of July and August reflects the easing of the warm summer breezes, hinting at the arrival of crisper days ahead. Notably, this period marks a transition from the gentle gusts typical in the earlier months, showing a consistent trend of lower wind speeds from June through October. As the landscape starts to change colors, the subtle, steady winds of September serve as a reminder of nature's quiet transformation, inviting you to breathe in the fresh, invigorating air of the approaching fall.

Average September Wind Speed in Minami-Alps

The chart displays monthly wind speed patterns in Minami-Alps, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.71.91.71.71.81.31.21.51.4 m/s1.41.51.7
Data source: Minami-Alps September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Minami-Alps Compares to Other Months

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

September weather presents a warm and humid atmosphere, with temperatures ranging from a cool 9°C (49°F) at night to a maximum of 31°C (89°F) during the day. This month is marked by significant precipitation, totaling 240 mm (9.5 inches) over 21 days, contributing to its 86% humidity. In contrast, January's climate is starkly colder, featuring temperatures that drop as low as -14°C (8°F), with an average of 0°C (32°F) and a maximum of 12°C (54°F). The winter month experiences much less rainfall, with only 59 mm (2.3 inches) recorded over just 6 days, and a lower humidity level of 76%. For more detailed information on the January weather conditions, visit Minami-Alps weather in January.

In comparing the weather of September and February, we observe significant contrasts in temperature and conditions. September boasts a warm average of 19°C (66°F), with maximums reaching up to 31°C (89°F), while February struggles with much colder temperatures, seeing a chilling average of just 1°C (34°F) and minimums dropping to -12°C (11°F). Additionally, September faces a high level of precipitation, totaling 240 mm (9.5 in) over 21 days, and humidity levels are elevated at 86%. In contrast, February experiences less rainfall at 76 mm (3.0 in) spread over only 9 days, accompanied by a lower humidity of 74%. For detailed insights on February conditions, you can check Minami-Alps weather in February.

September and March showcase strikingly different weather characteristics. In September, temperatures range from a refreshing 9°C (49°F) to a warm 31°C (89°F), with an average of 19°C (66°F). The month is quite humid at 86%, and the region experiences considerable precipitation of 240 mm (9.5 in) over 21 days. In contrast, March temperatures are much cooler, with a minimum of -6°C (21°F), an average of 5°C (42°F), and a maximum of 21°C (70°F). Precipitation is lower at 182 mm (7.2 in) across 14 days, and humidity is reduced to 70%. For a more detailed look at March weather patterns, visit Minami-Alps weather in March.

When comparing the weather in September and April, it becomes evident that September is generally warmer and more humid. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 31°C (89°F), with an average of 19°C (66°F). The month typically sees significant rainfall, with around 240 mm (9.5 in) of precipitation over 21 days, contributing to a high humidity level of 86%. In contrast, April experiences milder temperatures, starting as low as -5°C (24°F) and peaking at 24°C (76°F), with an average of 9°C (49°F). April also has less precipitation at 177 mm (7.0 in) over 15 days and a lower humidity of 74%. For more detailed information about April weather, you can visit Minami-Alps weather in April.

When comparing the weather in September and May, there are notable differences in temperature and precipitation. September boasts warmer temperatures, with a minimum of 9°C (49°F) and an average high of 31°C (89°F), while May experiences cooler conditions, ranging from a minimum of 0°C (33°F) and an average high of 28°C (82°F). September also has significantly higher precipitation, totaling 240 mm (9.5 in) over 21 days, compared to May’s 182 mm (7.1 in) across 14 days. Interestingly, despite the warmer temperatures, September has a slightly higher humidity level at 86% compared to May's 81%. For more details, you can check out Minami-Alps weather in May.

When comparing the weather in September and June, we find both months offer mild temperatures with a few notable differences. September presents a wider range of temperatures, with minimums reaching 9°C (49°F) and maximums climbing to 31°C (89°F), while June is slightly cooler, with minimums of 6°C (43°F) and maximums peaking at 29°C (85°F). Precipitation is relatively similar, with September receiving 240 mm (9.5 in) over 21 days, slightly more than June's 218 mm (8.6 in) across 18 days. Humidity is also comparable, with September at 86% and June slightly higher at 88%. For a closer look at June weather conditions, you can explore Minami-Alps weather in June.

In comparing the weather of September and July, notable differences emerge. September experiences a lower minimum temperature of 9°C (49°F) compared to July’s warmer minimum of 14°C (57°F), contributing to a more comfortable average of 19°C (66°F) against July's 22°C (71°F). While both months see high temperatures around 31°C (89°F) in September and 32°C (91°F) in July, July tends to be more humid, with a humidity level of 93% versus September's 86%. Precipitation is notably higher in July, totaling 412 mm (16.2 in) over 24 days, while September receives 240 mm (9.5 in) across 21 days. For those planning visits, detailed insights can be found in Minami-Alps weather in July.

In comparing the weather of September and August, we see notable differences in temperature and precipitation. September tends to be cooler, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 31°C (89°F), down from August's warmer range of 13°C (56°F) to 33°C (92°F). Precipitation levels in September are slightly higher at 240 mm (9.5 in) compared to August's 216 mm (8.5 in), and both months experience rain on an average of 21 days. Humidity also remains high, though it slightly decreases from 90% in August to 86% in September. For a more detailed overview, you can refer to Minami-Alps weather in August.

September and October showcase a notable shift in weather patterns. In September, temperatures range from a minimum of 9°C (49°F) to a maximum of 31°C (89°F), with an average of 19°C (66°F). The month is characterized by high humidity at 86% and significant precipitation of 240 mm (9.5 in) spread over 21 days. In contrast, October brings a cooler climate, with temperatures dropping to a minimum of 1°C (35°F) and reaching a maximum of 27°C (82°F), averaging 14°C (57°F). While October sees increased precipitation at 345 mm (13.6 in) over 19 days, the humidity decreases slightly to 83%. For a detailed look at the weather during this month, refer to Minami-Alps weather in October.

September and November present quite contrasting weather patterns. In September, temperatures range from a mild minimum of 9°C (49°F) to a warm maximum of 31°C (89°F), with an average of 19°C (66°F). This month experiences significant rainfall, totaling 240 mm (9.5 in) over 21 days, accompanied by high humidity levels of 86%. In stark contrast, November sees much cooler temperatures, with a minimum dropping to -4°C (25°F) and an average of only 8°C (46°F), while the maximum reaches 20°C (69°F). Precipitation is significantly reduced to 78 mm (3.1 in) over just 11 days, with humidity slightly lower at 80%. For more insights into November weather in the region, check out Minami-Alps weather in November.

In comparing the weather between September and December, a stark contrast emerges. September boasts a much warmer climate, with average temperatures around 19°C (66°F) and highs soaring up to 31°C (89°F). The month experiences significant rainfall, totaling 240 mm (9.5 in) over 21 days, accompanied by high humidity levels of 86%. In sharp contrast, December sees a drastic drop in temperatures, averaging just 2°C (36°F), with a maximum of 18°C (64°F) and a chilling minimum of -9°C (16°F). Precipitation in December is notably lower at 70 mm (2.8 in) over only 8 days, and the humidity decreases to 78%. For a more detailed perspective on how the weather unfolds in December, you can check out Minami-Alps weather in December.

Compare Minami-Alps's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Minami-Alps

As September unfolds in the Minami-Alps, the weather offers a captivating transition from the summer's warmth to the crispness of autumn. With maximum temperatures reaching a balmy 31°C and an average of comfortable 19°C, the month still retains some lingering heat while introducing cooler evenings that dip to about 9°C. However, this month is also marked by significant precipitation, with rain falling on nearly three-quarters of the days, resulting in a humid atmosphere with levels around 86%. This blend of warmth and moisture sets September apart, creating a lush, vibrant landscape that prepares the region for the enchanting colors of fall. For more detailed insights into the seasonal patterns, explore Minami-Alps Climate.