September Weather in Inawashiro, Japan

Last updated: August 21, 2025

Inawashiro, Japan, in September experiences a dynamic climate characterized by a broad temperature range, with maximums reaching up to 31°C (89°F) and minimums dipping to 9°C (48°F). The average temperature settles comfortably around 20°C (67°F), offering a pleasant backdrop for outdoor activities. However, visitors should be prepared for frequent showers, as the month brings 120 mm (4.7 in) of precipitation over approximately 14 days, contributing to a high humidity level of 89%. This blend of warmth and moisture creates a lush and vibrant atmosphere, making September an appealing time to explore the beauty of Inawashiro.

September Temperature in Inawashiro

In September, Inawashiro, Japan experiences a welcoming transition from summer's peak to the cool embrace of autumn. The minimum temperature hovers around 9°C (48°F), providing a refreshing start to the month, while the average temperature settles comfortably at 20°C (67°F), making it an ideal time for outdoor activities and exploring the stunning landscapes. As the days progress, the maximum temperature reaches a pleasant 31°C (89°F), offering warm afternoons that linger pleasantly without the oppressive heat of earlier summer months. This blend of mild temperatures creates a perfect environment for enjoying the region's natural beauty and vibrant autumn foliage, highlighting September as a delightful time to visit Inawashiro.

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

The chart illustrates September temperature patterns in Inawashiro, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Inawashiro, 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).
JanFebMarAprMayJunJulAugSepOctNovDec303139485965737667574636
Data source: Temperature data for Inawashiro 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 Inawashiro

In September, Inawashiro experiences a notable precipitation total of 120 mm (4.7 in), aligning with the heavier rainfall patterns observed in the summer months. This amount, although slightly less than the 239 mm (9.4 in) seen in July and 136 mm (5.3 in) in August, indicates that the region remains under the influence of late summer weather systems. With 14 precipitation days during the month, the rain is more evenly spread compared to the deluges of mid-summer, contributing to the transition into autumn. As we move into October, precipitation is expected to increase again, highlighting a seasonal shift where precipitation levels generally rise before tapering off in the winter. This pattern reflects a resilient climate rhythm, essential for supporting the local ecosystem and agricultural practices in the area.

September Precipitation Trends in Inawashiro

The chart displays monthly precipitation patterns in Inawashiro, 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 Inawashiro, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec96901201059910123913612016860110
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Inawashiro

Inawashiro, Japan, experiences noticeable variations in humidity throughout the year, with September standing out as a transitional month. Following the peak summer months of July and August, when humidity reaches an unwavering 92%, September sees a slight dip to 89%, yet it remains high. This decrease is part of a broader trend as the humidity gradually wanes into autumn, dropping to 87% in October. The overall pattern reveals a tendency for humidity levels to be highest in the summer, while late summer and early autumn witness a gentle easing as the seasons shift. Despite the slight decline, September's humidity still retains a palpable warmth, lingering as a reminder of the summer's embrace.

September Average Humidity in Inawashiro

This chart illustrates the average monthly humidity levels in Inawashiro, 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 Inawashiro is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec88%87%81%79%81%88%92%92%89%87%85%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Inawashiro

In September, Inawashiro, Japan, experiences a UV Index of 9, placing it in the very high exposure category. With a shorter burn time of just 15 minutes, this month signifies a transition from the extreme levels of summer. As we move from the peak UV intensity in July and August, where the UV Index consistently hit 11, September still maintains significant solar exposure. This trend underscores the importance of sun protection, especially as outdoor activities increase during the pleasant early autumn weather. For more detailed insights, visit Inawashiro UV Index.

Maximum UV Index Levels in Inawashiro for September

The chart shows the monthly maximum UV Index (UVI) for Inawashiro 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 Inawashiro typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec4589101111119753
Data source: Inawashiro 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 Inawashiro

September in Inawashiro, Japan, offers a delightful reprieve as the summer winds down, with 228 hours of sunshine gracing the region. This marks a slight dip from the vibrant summer months of July and August, which saw peaks of 246 and 271 hours, respectively. As the year progresses, we observe a trend where daylight hours gradually diminish, with October following suit at 193 hours. Nevertheless, September still outshines the earlier winter months, where sunlight often hovers around 145 hours in January. This gradual transition invites a unique beauty to the landscape, as autumn colors begin to emerge under the golden sun, making it an enchanting time for visitors and locals alike to celebrate the changing seasons.

Monthly Sunshine Duration in Inawashiro: September Highlighted

The September sunshine duration represents the total number of hours Inawashiro 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.
JanFebMarAprMayJunJulAugSepOctNovDec145h195h242h263h281h266h246h271h228h193h205h173h
Data source: Inawashiro September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Inawashiro During September

In Inawashiro, Japan, September presents a moderate 23% chance of sunny weather, making it one of the more stable months as summer transitions to autumn. This likelihood is consistent with the overall trend seen throughout the year, where the chance of sunny days fluctuates but never peaks dramatically. As the temperatures begin to cool from the humid summer months, September still holds onto a bit of that early autumn warmth. It stands out slightly against the preceding months, such as July and August, both of which have slightly lower chances of sunshine. Overall, while September does not guarantee bright skies, it offers a balanced opportunity for enjoying the beautiful landscape of Inawashiro.

Percentage of Sunny Days in September in Inawashiro

The chart illustrates the percentage of sunny days in Inawashiro 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 Inawashiro experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec16%29%27%41%25%21%23%22%23%27%33%22%
Data source: Inawashiro September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Inawashiro in September

In Inawashiro, Japan, September marks a gentle shift in daylight duration, offering approximately 12 hours of light—a subtle yet significant decline from the peak of 14 hours experienced during the summer months. As the year progresses from the vibrant days of May through August, where the sun lingers longest, September signals the transition into autumn with slightly shorter days. This gradual reduction continues into October and November, culminating in the cozy, shorter daylight hours of winter. The rhythmic cycle of daylight enhances the natural beauty of Inawashiro, making the early fall an enchanting time as the landscape gradually shifts into hues of gold and amber.

Average Daylight Hours in Inawashiro for September

The chart illustrates the variation in daylight duration in Inawashiro throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 52m10h 47m11h 57m13h 10m14h 11m14h 41m14h 26m13h 33m12h 23m11h 11m10h 8m9h 36m
Data source: Inawashiro daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Inawashiro

As autumn begins to sweep through Inawashiro, September marks a subtle shift in the air, with average wind speeds settling at a gentle 1.9 m/s (4 mph). This transitional month sees a slight increase from the summer lull, yet it still maintains a tranquil ambiance reminiscent of the quieter months preceding it. Following the summer's peak calm, where winds dipped to their lowest in July and August, September's breezes hold promise for the shifting seasons ahead. The winds then begin to pick up slightly in October and November, suggesting a gradual revitalization as the landscape prepares for the arrival of winter. The evolving wind patterns paint a picturesque narrative of change, underscoring the delicate balance of Inawashiro's seasonal climate.

Average September Wind Speed in Inawashiro

The chart displays monthly wind speed patterns in Inawashiro, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.53.32.82.92.51.71.41.91.9 m/s2.12.22.8
Data source: Inawashiro September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Inawashiro Compares to Other Months

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

September and January present contrasting weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 31°C (89°F), with an average of 20°C (67°F). The month experiences significant rainfall, totaling 120 mm (4.7 in) over about 14 days and maintaining high humidity at 89%. In contrast, January sees much chillier conditions, with temperatures ranging from a low of -11°C (12°F) to a high of 8°C (47°F), averaging around -1°C (31°F). Precipitation in January is slightly lower at 96 mm (3.8 in), distributed over 18 days, and the humidity stands at a comparable 88%. For more detailed information about January weather, visit Inawashiro weather in January.

September and February present stark contrasts in weather conditions. In September, temperatures range from a mild 9°C (48°F) at night to a warm average of 20°C (67°F), peaking at a hot 31°C (89°F) during the day. The month sees substantial rainfall, with 120 mm (4.7 in) of precipitation over approximately 14 days, contributing to a high humidity level of 89%. In contrast, February is marked by much colder temperatures, with nighttime lows plunging to -11°C (13°F) and daytime highs averaging around 0°C (32°F) before reaching a maximum of 15°C (59°F). Precipitation is lower, totaling 90 mm (3.5 in) but spread across 19 days, resulting in slightly lower humidity at 86%. These differences highlight the transition from the warmth of late summer to the chill of mid-winter. For more information on February weather, you can check Inawashiro weather in February.

September and March showcase contrasting weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a warm maximum of 31°C (89°F), with an average of 20°C (67°F). In contrast, March experiences much cooler conditions, with temperatures dipping as low as -9°C (16°F) and only peaking at 19°C (67°F), averaging around 4°C (39°F). Both months see similar precipitation levels, with September receiving 120 mm (4.7 in) over about 14 days, while March has slightly more rainfall spread over 15 days. Humidity levels are higher in September at 89%, compared to March's 81%, emphasizing the more comfortable yet damp feel of the early autumn month. For a detailed look at March conditions, you can check the link: Inawashiro weather in March.

September and April showcase distinct contrasts in weather patterns. September experiences warmer temperatures, with averages around 20°C (67°F) and maximums reaching 31°C (89°F), while April's temperatures are much cooler, averaging only 9°C (48°F) and peaking at 26°C (79°F). Both months see a fair amount of precipitation, with September receiving 120 mm (4.7 in) across 14 days, compared to April’s 105 mm (4.1 in) over 13 days. Humidity levels are notably higher in September at 89%, while April maintains a more comfortable 78%. For more detailed insights on the weather in April, you can visit Inawashiro weather in April.

When comparing the weather in September and May, notable differences emerge. September boasts warmer average temperatures, ranging from a minimum of 9°C (48°F) to a maximum of 31°C (89°F), while May experiences cooler temperatures, starting from a minimum of 2°C (36°F) and averaging at 15°C (59°F). Additionally, September tends to be wetter, with 120 mm (4.7 in) of precipitation over 14 days, compared to May's 99 mm (3.9 in) over 12 days. Furthermore, September has a higher humidity level of 89%, compared to May's 81%. For further details about May weather in Inawashiro, check out Inawashiro weather in May.

In comparing the weather of September and June, we see that September tends to be slightly warmer overall, with average temperatures reaching 20°C (67°F) compared to June's 18°C (66°F). Both months experience similar maximum temperatures, though September can reach up to 31°C (89°F), while June peaks at 32°C (90°F). In terms of precipitation, September is a bit wetter, receiving 120 mm (4.7 in) over approximately 14 days, while June has 101 mm (4.0 in) spread over 12 days. Humidity levels remain comparable, with September at 89% and June at 88%. For more specific details on weather patterns, you can check Inawashiro weather in June.

In comparing the weather of September and July, we can see distinct differences in temperature and precipitation. September experiences a cooler climate with a minimum temperature of 9°C (48°F) and an average of 20°C (67°F), while July boasts warmer temperatures, starting at a minimum of 14°C (58°F) and averaging 23°C (73°F). Precipitation also plays a significant role; September receives 120 mm (4.7 in) of rain over approximately 14 days, whereas July is much wetter with 239 mm (9.4 in) falling over 19 days. Humidity remains high in both months, with September at 89% and July slightly higher at 92%. For more detailed insights, check out Inawashiro weather in July.

In comparing the weather between September and August, September tends to be cooler with minimum temperatures dropping to 9°C (48°F) and an average of 20°C (67°F), while August remains warmer, with a minimum of 14°C (57°F) and an average of 24°C (76°F). The maximum temperatures in September peak at 31°C (89°F), slightly lower than August's maximum of 34°C (94°F). Precipitation is slightly less in September at 120 mm (4.7 in) over 14 days, compared to August, which receives 136 mm (5.3 in) across 16 days. Additionally, humidity levels are marginally lower in September at 89%, compared to August's 92%. For more detailed information, you can check Inawashiro weather in August.

September and October present a noticeable shift in weather patterns. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 31°C (89°F), with an average of 20°C (67°F). The month experiences 120 mm (4.7 in) of precipitation over 14 days, accompanied by high humidity at 89%. In contrast, October brings cooler temperatures, with a minimum of 2°C (37°F) and an average of 14°C (57°F), peaking at 27°C (80°F). Precipitation increases to 168 mm (6.6 in) over 12 days, while humidity remains relatively stable at 87%. This transition reflects the onset of autumn, making October significantly cooler and wetter compared to September. For more details, check out Inawashiro weather in October.

September and November present strikingly different weather profiles. In September, temperatures range from a mild 9°C (48°F) at night to a warm 31°C (89°F) during the day, with an average of 20°C (67°F). The month is characterized by high humidity at 89% and significant rainfall, with about 120 mm (4.7 in) spread over 14 days. In contrast, November brings a notable drop in temperature, with minimums plunging to -3°C (26°F) and an average of only 8°C (46°F). The maximum temperature reaches a maximum of 20°C (68°F), but overall, the month sees less precipitation at 60 mm (2.3 in) over 11 days and slightly lower humidity at 85%. For more detailed information, check out Inawashiro weather in November.

September and December present markedly different weather experiences. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 31°C (89°F), with an average of 20°C (67°F). This month sees significant precipitation of 120 mm (4.7 in) spread over 14 days, along with high humidity levels at 89%. In contrast, December brings colder conditions, with minimum temperatures plunging to -10°C (15°F) and a maximum of 17°C (62°F), resulting in an average of just 2°C (36°F). Although the precipitation is slightly lower at 110 mm (4.3 in) across 20 days, the humidity also drops to 86%. For more detailed information on December weather, you can visit Inawashiro weather in December.

Compare Inawashiro's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Inawashiro

As September arrives in Inawashiro, the weather transforms with a noticeable shift from the summer heat to cooler autumn days. Daytime temperatures can still reach a warm 31°C, but the nights can be quite refreshing with lows approaching 9°C. This month often sees an increase in precipitation, averaging around 120 mm, making it one of the wetter months with about half the days experiencing some rainfall. Additionally, the high humidity levels can make the air feel dense, contrasting sharply with the drier summer months. This blend of warm days, cool nights, and increased moisture creates a unique transitional climate that invites outdoor activities and showcases the beauty of early autumn in Inawashiro. For more detailed insights, check out Inawashiro Climate.