Last updated: August 21, 2025
Oshu, Japan experiences a remarkable September, where temperatures range from a maximum of 33°C (91°F) to a minimum of 4°C (39°F), creating a diverse weather tapestry. The month averages around 19°C (67°F), offering warm days tempered by cooler nights. With 117 mm (4.6 in) of rainfall across 12 days, humidity levels soar to 86%, contributing to a lush, vibrant atmosphere. This blend of warmth and moisture characterizes September as an enchanting time to explore the rich landscapes and cultural offerings of Oshu.
In September, Oshu, Japan, experiences a delightful transition into early autumn. The temperatures mark a noticeable shift from the summer's heat, with minimums dipping to 4°C (39°F) and averaging 19°C (67°F), perfect for enjoying the crispness in the air. Daytime highs can still reach a warm 33°C (91°F), allowing for plenty of sunshine before the cooler months set in. As the month progresses, the warm summer days slowly give way to the refreshing chill of fall, making September an ideal time for outdoor activities and appreciating nature's vibrant changes. This blend of warmth and coolness sets a picturesque scene, emphasizing the unique seasonal rhythm of this charming region.
In September, Oshu experiences a noteworthy transition in its weather pattern as precipitation levels settle at 117 mm (4.6 in) over 12 days. This marks a decrease from the intense rains of July and August, which both exceeded 160 mm, indicating a gradual shift from the summer monsoon season. While September's rainfall is substantial, it signifies the onset of autumn, with conditions becoming more temperate. This reduction in both total precipitation and the number of rainy days suggests a clear trend towards drier weather as the region prepares for October, which sees a slight uptick in rainfall again at 154 mm (6.1 in). Overall, September provides a more balanced weather experience, blending the remnants of summer's warmth with the cooler embrace of fall, paving the way for the changing seasons ahead.
September in Oshu, Japan, experiences a notable humidity level of 86%, maintaining the trend of elevated moisture that characterizes the summer months. Following the peaks of July and August, where humidity reaches a high of 92%, September shows a slight decrease, but still remains comfortably humid compared to the beginning of the year. This month marks a transition, as it blends the lingering warmth of summer with the approaching coolness of autumn. The gradually diminishing humidity from July to September, paired with the monthly average of 80% seen in early winter, hints at the cyclical nature of Oshu's climate, where seasons shift gracefully but maintain a consistent high level of atmospheric moisture.
As September unfolds in Oshu, Japan, the UV Index remains highly significant, registering at 9 and categorized as very high. This trend follows an intense summer where the UV Index peaked at 10 for several months, demanding caution with only 15 minutes of exposure before sunburn risk escalates. As the season transitions into fall, the UV levels slightly decrease but still require vigilance, especially for outdoor enthusiasts. Be sure to stay protected, as the weather may still invite plenty of outdoor activities. For more details on the UV Index throughout the year, check out Oshu UV Index.
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September in Oshu, Japan, offers a delightful transition into autumn with 239 hours of sunshine, marking a gentle decline from the vibrant summer months. As the sun begins its retreat, daylight hours settle after the height of May, which boasts 290 hours of radiant sunshine. Following a consistent pattern, September’s sunshine is slightly less than the preceding months of July and August, both at 251 hours, but still outshines the earlier winter months. This gradual shift paints a picture of nature's rhythm, as Oshu prepares for cooler days while still basking in the warm hues of early fall. Embrace the beauty of September’s sunlight as it continues to illuminate the scenic landscapes of Oshu, inviting reflection and renewal before the shorter days of October.
In Oshu, Japan, September experiences a moderate 27% chance of sunny weather, offering a slight reprieve from the summer's gray skies. As the months progress, the likelihood of sunshine generally declines, reaching its lowest points in the peak summer months of July and August, with only 20% and 18% sunny days, respectively. Interestingly, September follows a trend of gradually increasing sun chances as the year transitions into autumn, but it still lags behind the brighter months of spring and early winter, which boast around 30% to 43% sunny days. As a result, while September may not offer the best odds for sun-seekers, it presents a chance for breezy days and the beautiful hues of early fall.
In Oshu, Japan, the daylight duration begins its gradual decline in September, offering 12 hours of sunlight as the summer months fade into autumn. This marks a shift from the peak summer months of June, July, and August, where daylight extends to a robust 14 hours, fostering long, bright days perfect for outdoor activities. As September arrives, the daylight starts to wane, but the transition isn't abrupt; it reflects a gentle progression from 14 hours in the summer to 11 hours by October. Following this pattern, the daylight continues to diminish, reaching its shortest span of 9 hours in both January and December. This rhythmic cycle highlights the balance of nature's light throughout the year, offering Oshu's residents a beautiful variety of seasonal experiences.
In September, Oshu, Japan, experiences a gentle breeze, with the average wind speed settling at 2.1 m/s (5 mph), consistent with the calmer conditions seen in August. This tranquility marks a notable shift from the windier months of winter and early spring. Throughout the year, wind speeds peaked in the earlier months, with January reaching 2.8 m/s and February at 3.7 m/s. As the seasons transitioned, a gradual decline occurred, culminating in the summer months where July recorded its lowest at 1.8 m/s. As we move into autumn, the wind begins to pick up again slightly, remaining steady in the fall months of October and November. This pattern reflects a harmonious cycle in the local climate, where a blend of gentle winds and seasonal shifts shapes Oshu's atmospheric character.
Weather in Oshu varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Oshu, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather conditions. In September, temperatures range from a chilly 4°C (39°F) at night to a warm 33°C (91°F) during the day, with an average of 19°C (67°F). The month sees considerable rainfall, totaling 117 mm (4.6 in) over 12 days, coupled with high humidity levels of 86%. In contrast, January grips the region with frigid temperatures, dipping as low as -22°C (-8°F) and averaging a mere -2°C (30°F), reaching a maximum of only 7°C (45°F). Precipitation is less frequent, amounting to 56 mm (2.2 in) over the same number of days, and humidity is slightly lower at 80%. For more details on January weather, you can visit Oshu weather in January.
September and February exhibit stark contrasts in weather patterns. September features a broad temperature range, with minimums of 4°C (39°F), average highs around 19°C (67°F), and maximums peaking at 33°C (91°F), accompanied by high humidity levels at 86% and considerable precipitation of 117 mm (4.6 in) over 12 days. In contrast, February is characterized by a much colder climate, with temperatures ranging from a minimum of -18°C (0°F) to a maximum of 11°C (52°F) and an average of -1°C (31°F). Although it experiences less precipitation, totaling 69 mm (2.7 in) across 14 days, the humidity is lower at 79%. For more detailed weather information for Oshu in February, visit Oshu weather in February.
September and March present quite contrasting weather conditions. September sees a range of temperatures from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), with an average of 19°C (67°F). It is relatively humid, with an average humidity of 86% and approximately 117 mm (4.6 in) of precipitation over 12 days. In contrast, March is much cooler, with temperatures ranging from a minimum of -12°C (11°F) to a maximum of 20°C (68°F) and an average of just 4°C (39°F). Although it experiences a similar level of precipitation at 106 mm (4.2 in) over 14 days, the humidity is lower at 77%. For more insights on the weather in March, check out Oshu weather in March.
When comparing the weather between September and April, notable differences emerge. September typically offers a wider range of temperatures, with a minimum of 4°C and a maximum reaching up to 33°C, resulting in an average of 19°C. The month also experiences high humidity at 86% and about 117 mm of precipitation over approximately 12 days. In contrast, April showcases cooler conditions, with temperatures ranging from a minimum of -6°C to a maximum of 25°C, averaging 8°C. Despite having slightly higher precipitation at 119 mm, it spreads over about 15 days, and humidity is lower at 75%. For more on what to expect in April, check out Oshu weather in April.
In comparing the weather of September and May, we see that September tends to be warmer, with maximum temperatures reaching up to 33°C (91°F) compared to May's high of 30°C (87°F). The average temperature in September is also notably higher at 19°C (67°F), versus May's average of 14°C (58°F). Both months experience a similar amount of precipitation, around 114-117 mm, with September seeing slightly more rainfall over 12 days compared to May's 13 days. Additionally, September has a higher humidity level at 86%, while May's is more moderate at 80%. For a detailed look into the weather during May, you can check out Oshu weather in May.
September and June exhibit distinct weather characteristics, with September showcasing a wider temperature range and slightly warmer average highs. In September, temperatures can dip as low as 4°C (39°F) and peak at 33°C (91°F), whereas June has milder minimums of 7°C (44°F) and a maximum of 30°C (87°F). Precipitation levels are relatively similar, with September receiving 117 mm (4.6 in) over 12 days and June experiencing 129 mm (5.1 in) across 14 days. Humidity levels are also comparable, remaining high in both months at around 86% for September and 87% for June. For a more in-depth look at June's weather, visit Oshu weather in June.
In comparing the weather of September and July, a notable difference emerges in temperature ranges and overall conditions. September experiences cooler temperatures, with a minimum of 4°C (39°F) and an average of 19°C (67°F), while July enjoys warmer nights with a minimum of 14°C (57°F) and an average of 22°C (72°F). Both months reach similar maximum temperatures, peaking at 33°C (91°F) in September and 33°C (92°F) in July, but July sees significantly higher precipitation at 182 mm (7.2 in) over 17 days, compared to September's 117 mm (4.6 in) over 12 days. Additionally, humidity levels are slightly higher in July at 92%, contrasted with September's 86%. For more detailed information on July weather, you can visit Oshu weather in July.
In September, the weather tends to be cooler than in August, with minimum temperatures dropping to 4°C (39°F) compared to August's milder 10°C (51°F). The average temperature in September is 19°C (67°F), while August boasts a higher average of 23°C (74°F). Additionally, September experiences slightly less precipitation at 117 mm (4.6 in) over 12 days, whereas August sees more rain, totaling 167 mm (6.6 in) over 18 days. This shift results in a decrease in humidity as well, with September's humidity at 86% compared to August's 92%. For more details on weather trends, you can visit Oshu weather in August.
September and October present a noticeable shift in weather patterns. September sees a broader temperature range, with minimums around 4°C (39°F) and maximums reaching up to 33°C (91°F), providing warmer days with an average of 19°C (67°F). In contrast, October's temperatures cool down significantly, featuring minimums of 0°C (33°F) and maximums of 27°C (80°F), averaging only 13°C (55°F).
Precipitation also sees an increase in October, rising to 154 mm (6.1 in) compared to September's 117 mm (4.6 in), despite having the same number of rainy days—12. Additionally, humidity levels slightly decrease from 86% in September to 82% in October, contributing to the overall feeling of crispness in the air. For more detailed information, you can check Oshu weather in October.
September weather is characterized by much warmer temperatures, with averages around 19°C (67°F) and highs reaching up to 33°C (91°F). In contrast, November sees a significant drop, with average temperatures dropping to 6°C (44°F) and maximums only reaching 19°C (66°F). While September is marked by higher humidity at 86% and more precipitation, totaling 117 mm (4.6 in) over 12 days, November is drier, bringing only 56 mm (2.2 in) of rain over 10 days and lower humidity at 79%. For a more detailed look at November in Oshu, you can visit Oshu weather in November.
September and December present a stark contrast in weather conditions. September features a significant temperature range with minimums around 4°C (39°F) and maximums peaking at 33°C (91°F), resulting in an average of 19°C (67°F). The month also sees high humidity at 86% and a total rainfall of 117 mm (4.6 in) over 12 days. In contrast, December brings much colder temperatures, with a minimum of -10°C (14°F) and a maximum of only 14°C (58°F), leading to an average of just 1°C (33°F). Though it experiences slightly lower precipitation of 78 mm (3.1 in), December has more rainy days, totaling 17. For more details on December weather specifically, visit Oshu weather in December.
In September, Oshu experiences a striking transition from the sweltering summer heat, with maximum temperatures peaking at 33°C, to more refreshing autumn days where the average temperature settles at a comfortable 19°C. This month stands out not only for its fluctuating temperatures but also for its notable precipitation, accumulating 117 mm over 12 days, which contributes to the region’s lush landscape. With humidity levels rising to 86%, September is marked by a softer, more humid climate compared to the drier months of summer, making it an intriguing time to experience the beauty of Oshu. For a deeper dive into what to expect throughout the year, visit Oshu Climate.