Last updated: August 21, 2025
In Hachioji, Japan, September brings a blend of warmth and moisture, with maximum temperatures reaching up to 35°C (94°F) and an average of 22°C (71°F). While the days can be hot, evenings offer a refreshing respite as temperatures cool to a minimum of 12°C (53°F). This month also sees significant precipitation, accumulating 247 mm (9.7 in) over 22 days, contributing to the region’s lush greenery. High humidity levels at 86% create a humid atmosphere, typical of late summer's transition to autumn, making it a unique and vibrant time in Hachioji.
In September, Hachioji, Japan transitions beautifully from the sweltering summer heat to the mild embrace of autumn. With temperatures ranging from a minimum of 12°C (53°F) to a maximum of 35°C (94°F), the month retains warmth while introducing a refreshing coolness in the evenings. The average temperature sits comfortably at 22°C (71°F), a pleasant balance that encourages outdoor excursions and the enjoyment of nature's transformation. Compared to the scorching highs of August, which peak at 36°C (97°F), September marks a welcome respite, inviting residents and visitors alike to savor the rich hues of the season and the crispness of the air that hints at the changing days ahead.
September in Hachioji, Japan, marks a significant shift in the rainfall pattern, with precipitation totaling 247 mm (9.7 in)—the highest amount for the month, reflecting the region's transition into the wetter autumn season. This increase in rainfall follows a series of summer months characterized by substantial downpours, with July peaking at 312 mm (12.3 in), indicative of both the monsoon influence and tropical systems. Throughout September, rain graces the city on 22 days, creating a tapestry of lush landscapes and vibrant autumn foliage. As temperatures begin to cool and humidity lessens, residents welcome the rains, appreciating the freshness they bring to the air while providing a vital lifeline for the lush greenery that surrounds Hachioji.
September in Hachioji, Japan, maintains a high level of humidity, averaging 86%. As summer transitions into autumn, the humidity begins to taper from the peak levels experienced in July and August, which soar at 93% and 90%, respectively. This slight decline marks a shift from the oppressive summer heat, yet September remains notably humid compared to the earlier months of the year, where humidity hovered around the low to mid-70s. The increased moisture in the air during September sets the stage for the changing seasons, as the region gradually prepares for the drier months ahead in October and November.
As September rolls into Hachioji, Japan, the UV Index remains a prominent factor in your outdoor plans, registering at 10—a notch below the peak summer levels. This very high exposure category indicates that while the scorching summer months of June through August maintain an extreme UV Index of 11, September still demands caution with a burn time of only 15 minutes. It's a reminder that even as the air cools, the sun's intensity can still pose risks for unprotected skin. Regularly checking the UV Index, especially during this transitional month, is vital for safety and enjoyment under the sun. For more insights on the UV levels throughout the year, visit Hachioji UV Index.
UV Risk Categories
September in Hachioji, Japan, delivers a pleasant retreat into the lingering warmth of early autumn, basking in an impressive 235 hours of sunshine. This month, while slightly less radiant than the sun-drenched August with its 284 hours, retains a comfortable luminosity that smoothly transitions from the summer glow. As daylight begins to retreat with the arrival of October, which sees a dip to 205 hours, September serves as a gentle reminder of the vibrant sun-filled days of the preceding months. Notably, this month’s sunshine hours, although reduced, outshine those of June and July, showcasing a season still brimming with brightness before the cooler months set in.
September in Hachioji, Japan, marks a transitional period as the summer heat begins to wane. With only a 21% chance of sunny weather, it’s one of the more overcast months, following a slightly brighter August and preceding the more favorable conditions of October. This dip in sunshine likelihood reflects a broader trend of decreasing chances as the seasons shift from summer's peak to autumn’s embrace. As the year progresses, sunny days become increasingly rare, peaking in mid-winter with a 57% chance in January, yet September stands out for its notable shift towards cloudier skies, inviting a more subdued outdoor atmosphere.
As September unfolds in Hachioji, Japan, the landscape begins to shift with the gradual transition from the vibrant summer days. With approximately 12 hours of daylight, the month marks a slight decline from the peak summer months of July and August, which boasted 14 hours of sunshine. This gentle decrease is part of a noticeable trend, as daylight steadily wanes from the summer solstice onwards, leading into the shorter days of autumn. By month’s end, residents can expect to enjoy a balanced blend of daylight, while anticipating the cozy embrace of the upcoming seasonal changes.
In Hachioji, Japan, the winds in September bring a gentle breeze, with an average speed of 1.7 m/s (4 mph). This slight dip from the summer months reflects a gradual transition as the region steps into autumn. From the breezy heights of March and April, where winds reach around 2.4 m/s (5 mph), there is a notable decrease through the summer, with winds mellowing to 1.5 m/s (3 mph) in July. As September arrives, the winds begin to strengthen slightly again towards October, hinting at the seasonal shifts ahead. This pattern showcases the rhythmic nature of Hachioji's climate, where gentle winds weave through the changing seasons, providing a soothing backdrop to the vibrant landscape.
Weather in Hachioji varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Hachioji, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is warm and humid, with temperatures ranging from a mild 12°C (53°F) at night to a scorching 35°C (94°F) during the day, and an average temperature of 22°C (71°F). This month also sees considerable rainfall, with 247 mm (9.7 in) of precipitation over 22 days, contributing to the high humidity levels of 86%. In stark contrast, January experiences a much colder climate, where temperatures can drop as low as -13°C (9°F), with a daily average of just 3°C (37°F) and a maximum of 17°C (63°F). Precipitation is significantly lower, totaling 53 mm (2.1 in) over only 7 days, and the humidity sits at a more moderate 76%. For a more detailed comparison, you can visit Hachioji weather in January.
September and February present strikingly different weather patterns. In September, temperatures range from a mild 12°C (53°F) to a warm 35°C (94°F), with an average around 22°C (71°F). This month experiences significant rainfall, totaling 247 mm (9.7 in) over about 22 days, and high humidity at 86% keeps the atmosphere quite muggy. In contrast, February features a much cooler climate, with temperatures dropping to a minimum of -6°C (21°F) and averaging just 4°C (40°F), peaking at a maximum of 21°C (69°F). Precipitation is much lower in February, at 62 mm (2.4 in) over approximately 10 days, with humidity levels around 74%. For more detailed insights on February weather, visit Hachioji weather in February.
When comparing the weather in September and March, distinct differences emerge. September boasts warmer temperatures, ranging from a minimum of 12°C (53°F) to a maximum of 35°C (94°F), with an average temperature of 22°C (71°F). It also tends to be quite humid, with an average humidity of 86% and considerable precipitation of 247 mm (9.7 in) over 22 days. In contrast, March experiences much cooler conditions, featuring temperatures that range from a chilly -4°C (26°F) to a milder 23°C (73°F) with an average of 8°C (47°F). The month sees less rainfall, totaling 166 mm (6.5 in) across 14 days, and the humidity is lower at 70%. For a detailed look at Hachioji's March weather, check out Hachioji weather in March.
In September, the weather is significantly warmer compared to April, with average temperatures reaching 22°C (71°F) and maximums climbing to a sweltering 35°C (94°F). The month is also characterized by high humidity at 86% and considerable rainfall, averaging 247 mm (9.7 in) over 22 days. In contrast, April experiences cooler temperatures, with an average of 12°C (54°F) and highs reaching 26°C (79°F). Rainfall is lighter in April, totaling about 150 mm (5.9 in) over 15 days, and the humidity is lower at 74%. For more detailed insights, you can check Hachioji weather in April.
In comparing the weather between September and May, it’s clear that September tends to be warmer and wetter. September boasts an average temperature of 22°C (71°F) with highs reaching up to 35°C (94°F), while May is cooler, averaging 17°C (64°F) and peaking at 30°C (86°F). Additionally, September experiences significantly more precipitation, with 247 mm (9.7 in) over 22 days, compared to May’s 148 mm (5.8 in) across 15 days. The humidity levels are also higher in September at 86%, compared to 81% in May. For more detailed information on May weather, you can visit Hachioji weather in May.
In September, the weather in Hachioji tends to be warmer with higher maximum temperatures reaching up to 35°C (94°F), compared to June's peak of 31°C (88°F). The average temperature in September is slightly higher at 22°C (71°F) versus June's 20°C (69°F). September also experiences more precipitation, totaling 247 mm (9.7 in) over 22 days, compared to June's 209 mm (8.2 in) over 19 days. Despite the warmer conditions in September, both months exhibit high humidity levels, with September at 86% and June at 88%. For more detailed insights, you can check Hachioji weather in June.
In comparing the weather patterns of July and September, we see notable differences in temperature and precipitation. September typically enjoys slightly cooler temperatures, with an average of 22°C (71°F) compared to July's warmer average of 24°C (76°F). However, both months can reach maximum temperatures around 35°C (95°F).
Precipitation is more pronounced in July, with a total of 312 mm (12.3 in) over 24 days of rain, compared to September's 247 mm (9.7 in) across 22 days. Additionally, humidity remains higher in July at 93% compared to September's 86%, making July feel more oppressive. For a detailed look into July weather, you can visit Hachioji weather in July.
In comparing the weather of September and August, we find notable differences in temperature and precipitation patterns. September sees slightly lower minimum and average temperatures, with a range from 12°C (53°F) to a maximum of 35°C (94°F), contrasted with August’s warmer minimum of 15°C (59°F) and an average of 26°C (79°F). Additionally, September experiences higher rainfall, recording 247 mm (9.7 in) over 22 days, compared to August's 195 mm (7.7 in) over 23 days. Humidity is also slightly less in September at 86%, while August maintains a higher level at 90%. For a detailed look at August weather in Hachioji, you can visit Hachioji weather in August.
September and October showcase a noticeable shift in weather patterns. September features warmer temperatures, with a minimum of 12°C (53°F) and an average of 22°C (71°F), peaking at 35°C (94°F). In contrast, October sees cooler temperatures, dropping to a minimum of 5°C (41°F) with an average of 16°C (61°F) and a maximum of 30°C (86°F).
Precipitation also increases in October, reaching 346 mm (13.6 in) over 19 days, compared to September's 247 mm (9.7 in) over 22 days. Although humidity is slightly lower in October at 83%, it remains relatively high. For more information on October weather specifics, you can visit Hachioji weather in October.
In September, the weather is significantly warmer, with temperatures ranging from a minimum of 12°C (53°F) to a high of 35°C (94°F), averaging 22°C (71°F). The month is also marked by high humidity at 86% and substantial precipitation, totaling 247 mm (9.7 in) over 22 days. In contrast, November brings a notable drop in temperature, with a minimum of -1°C (30°F) and an average of 11°C (52°F), peaking at 23°C (73°F). The precipitation is much lighter at 72 mm (2.8 in) over just 10 days, along with slightly lower humidity at 80%. Overall, September offers a much warmer and wetter climate compared to the cooler, drier conditions of November. For more detailed information, check out Hachioji weather in November.
The weather in September is characterized by warmer temperatures, with a minimum of 12°C (53°F) and an average of 22°C (71°F), reaching highs of 35°C (94°F). This month also sees a significant amount of precipitation, totaling 247 mm (9.7 in) over 22 days, coupled with a high humidity level of 86%. In contrast, December presents a much colder climate, with temperatures ranging from a minimum of -5°C (23°F) to an average of 5°C (42°F), peaking at 20°C (69°F). Precipitation decreases substantially to 62 mm (2.4 in) across just 9 days, and humidity drops to 78%. For more details on the December weather, you can visit Hachioji weather in December.
As September rolls in, Hachioji experiences a notable shift in weather, moving away from the sweltering heat of summer. Temperatures are more moderate, offering a refreshing average of 22°C (71°F), while the month is marked by an increase in humidity that can make the air feel heavier. Frequent rainfall, with 22 days of precipitation accumulating to 247 mm (9.7 in), contributes to the lush greenery that characterizes this transitional period. This combination of increased moisture and warmth sets September apart, creating a unique atmosphere that invites both local residents and visitors to embrace the beauty of autumn. For a deeper dive into the climate trends throughout the year, visit Hachioji Climate.