Last updated: August 21, 2025
In September, Unzen, Japan experiences a blend of warm temperatures and significant rainfall, making it a vibrant time for nature enthusiasts. With maximum temperatures peaking at 35°C (94°F) and an average of 25°C (78°F), the days can be quite sultry. However, nights offer a refreshing contrast, cooling down to a minimum of 16°C (62°F). The region receives 228 mm (9.0 in) of precipitation over 15 days, resulting in an humidity level of 84%, which enhances the lush landscape. Visitors can enjoy the beauty of early autumn while being prepared for the occasional shower, making it a perfect season for exploring the area's natural wonders.
September in Unzen, Japan, presents a delightful transition from the summer swelter to the more temperate autumn days. With minimum temperatures settling around 16°C (62°F), the month offers a refreshing reprieve from the peaks of August, where the mercury soared to 39°C (102°F). The average temperature rises to a comfortable 25°C (78°F), making it an ideal time for outdoor exploration. As the month progresses, maximum temperatures reach up to 35°C (94°F), still warm but significantly lower than the summer's scorching highs. This gradual cooling trend not only enhances the beauty of Unzen's lush landscapes but also invites visitors to enjoy its natural wonders in pleasant weather. Overall, September strikes a harmonious balance, bridging the exuberant heat of summer and the cooler embrace of autumn.
September in Unzen, Japan, marks a transition into the wetter autumn months, showcasing an impressive 228 mm (9.0 in) of rainfall over 15 days. This notable precipitation, while slightly less than that of July and August, still contributes to the region’s lush landscapes. The trend clearly indicates that September remains a significant month for rainfall, setting the stage for a gradual decrease in moisture as the year progresses into drier October. With the summer heat receding, the showers in September play a crucial role in refreshing the environment, preparing it for the cooler months ahead.
September in Unzen, Japan, offers a notable transition in humidity levels, reaching 84%, which is slightly lower than the steamy heights of 92% and 91% experienced in July and August, respectively. This decline marks a gradual easing from summer's oppressive moisture, reminiscent of the earlier months of the year when humidity hovered around 71% to 75%. As autumn approaches, the humidity gently dips further into October, settling at 83%. This consistent pattern underscores Unzen’s dynamic climate, where summer's humidity starts to fade, paving the way for a more comfortable fall experience.
September in Unzen, Japan, sees the UV Index standing at 11, marking it as an extreme exposure category with a burn time of just 10 minutes. This trend reflects the lingering summer intensity, where monthly UV levels remain elevated, peaking at 12 in July and August. As autumn approaches, the UV Index gradually declines, dropping to 7 by October, indicating a safer time for outdoor activities. Residents and visitors alike should remain vigilant during September, protecting themselves from the stronger sun. For more detailed information, check the Unzen UV Index.
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September in Unzen, Japan, showcases an inviting balance of sunshine, with 257 hours of brilliant light gracing the skies. As the summer peak in August yields 300 hours, September feels like a gentle transition into autumn, where daylight begins to wane but remains generous. This month's sunshine reflects a slight dip from the summer peak, yet it still outshines the earlier months of the year, maintaining a delightful warmth that encourages outdoor exploration. Following this sunny month, October brings a close contest with 258 hours, hinting at a modest consistency in daylight. The overall trend indicates that while the days shorten, September remains a radiant gem on Unzen's calendar, perfect for savoring the lingering warmth of late summer.
In September, Unzen, Japan, experiences a 34% chance of sunny weather, which shows a slight improvement from the more overcast summer months, particularly July and June where sunny days dipped to 20% and 21% respectively. This marks a gradual transition into the autumn season, as the likelihood of sunshine begins to rise again, especially when compared to May's low of 28%. Looking ahead, October brings a notable surge in sunny opportunities with a forecasted 64%, suggesting that while September offers some warmth and light, the real brightness of fall awaits just around the corner.
As September arrives in Unzen, Japan, the daylight gradually begins to wane, offering a gentle transition from the long, sunlit days of summer. With 12 hours of daylight, September marks a notable decline from the peak of 14 hours experienced in both June and July. This gradual ebb of sunlight is mirrored in the changing seasons, as autumn looms on the horizon, drawing closer to the shorter days of October and November. The shift from the vibrant brightness of summer to the crisp, cooler days of fall is a reminder of nature's rhythm, inviting residents and visitors alike to enjoy the beauty that accompanies this softer light.
As September unfurls in Unzen, Japan, the average wind speed gently dips to 2.3 m/s (5 mph), reflecting the transitional nature of the season. This subtle shift marks a departure from the summer breezes, which hovered around 2.7 m/s (6 mph) in August. Interestingly, the trend reveals that wind speeds tend to peak during the colder months, with January and February showcasing slightly stronger gusts at 3.0 m/s and 3.1 m/s respectively. The mellow September winds signal the approach of autumn, inviting the vibrant foliage and cooler temperatures that define this picturesque Japanese landscape. Overall, the gradual decline in wind speed from late summer to early fall evokes a serene, contemplative atmosphere, perfect for enjoying the majestic scenery Unzen has to offer.
Weather in Unzen varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Unzen, focusing on differences in temperature, rainfall, humidity, and UV levels.
September weather features warm temperatures, with minimums around 16°C (62°F) and maximums reaching up to 35°C (94°F), making it a very warm month with an average of 25°C (78°F). However, it also brings considerable rainfall, with about 228 mm (9.0 in) falling over 15 days, resulting in high humidity levels at 84%. In contrast, January offers a much cooler climate, with temperatures dipping as low as -2°C (29°F) and averaging around 8°C (46°F). The month experiences significantly less precipitation, totaling 53 mm (2.1 in) over only 6 days, and has a lower humidity level of 75%. For a closer look at what to expect this winter, check out Unzen weather in January.
In September, the weather is characterized by warm temperatures, with minimums around 16°C (62°F) and daytime highs reaching up to 35°C (94°F). The month sees considerable rainfall, accumulating 228 mm (9.0 inches) over about 15 days, contributing to a high humidity level of 84%. In contrast, February experiences much cooler conditions, with temperatures ranging from a frigid minimum of -2°C (29°F) to a comfortable maximum of 22°C (71°F) and an average of 8°C (48°F). Precipitation is also significantly lower, totaling 92 mm (3.6 inches) over 9 days, accompanied by a humidity level of 71%. For more detailed information on February weather, you can check Unzen weather in February.
September and March showcase contrasting weather patterns. In September, temperatures range significantly, with a minimum of 16°C (62°F) and a maximum of 35°C (94°F), averaging around 25°C (78°F). This month is characterized by higher humidity at 84% and considerable rainfall, totaling 228 mm (9.0 in) over 15 days. In contrast, March experiences cooler temperatures, with a minimum of 3°C (37°F) and a maximum of 24°C (76°F), averaging just 12°C (55°F). Precipitation is lower in March, amounting to 145 mm (5.7 in) over 11 days, accompanied by reduced humidity at 71%. For a more detailed look at the March weather, check out Unzen weather in March.
September and April present contrasting weather patterns. In September, temperatures range from a minimum of 16°C (62°F) to a maximum of 35°C (94°F), with an average of 25°C (78°F). This month experiences significant rainfall, totaling 228 mm (9.0 in) over 15 days, while the humidity remains high at 84%. In contrast, April is much cooler, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 29°C (84°F) and an average of 16°C (62°F). Precipitation in April is also lower at 135 mm (5.3 in) spread over 8 days, with humidity at a slightly lower 78%. For more details, you can check Unzen weather in April.
September and May present distinct weather experiences, characterized by varying temperatures and precipitation levels. In September, temperatures typically range from a minimum of 16°C (62°F) to a maximum of 35°C (94°F), with an average of 25°C (78°F). This month sees a significant amount of rainfall, totaling 228 mm (9.0 in) over about 15 days, while the humidity remains high at 84%. In contrast, May offers cooler temperatures, with a minimum of 10°C (50°F), an average of 21°C (69°F), and a maximum of 30°C (86°F). Although May has slightly less rainfall at 214 mm (8.4 in) over approximately 12 days, the humidity remains consistent at 84%. For more details on May weather specifically, you can check out Unzen weather in May.
When comparing the weather in September and June, one can observe several similarities and differences. Both months experience a minimum temperature of around 16°C (62°F), but June has a slightly lower average temperature of 24°C (75°F) compared to September's 25°C (78°F). In terms of maximum temperatures, September peaks at 35°C (94°F), making it hotter than June, which maxes out at 32°C (90°F). Precipitation levels are notable in both months, with June receiving 262 mm (10.3 in) of rainfall over 15 days, while September has slightly less rain at 228 mm (9.0 in) but also spans 15 days of precipitation. Humidity levels are similar too, with September at 84% and June at 86%. For those interested in a deeper dive, you can find more details at Unzen weather in June.
In comparing the weather of September and July, September generally offers slightly cooler temperatures, with average highs of 25°C (78°F) compared to July's warmer average of 27°C (82°F). While both months experience significant rainfall, July sees more with 475 mm (18.7 in) over 19 days, versus September's 228 mm (9.0 in) across 15 days. Additionally, humidity is slightly lower in September at 84% compared to 92% in July, which may make for a more comfortable experience. For a closer look at July conditions, visit Unzen weather in July.
September weather shows a noticeable shift from August, with a decrease in average temperature from 29°C (85°F) to 25°C (78°F). While September's maximum temperature can still reach 35°C (94°F), it is cooler than August's peak of 39°C (102°F), indicating a gradual transition toward fall. Precipitation also remains significant in September, measuring 228 mm (9.0 in) over 15 days, although it is somewhat less than August's 303 mm (11.9 in) across 14 days. Humidity is slightly lower in September at 84%, compared to 91% in August, providing a bit of relief as summer begins to fade. For more detailed information, check out Unzen weather in August.
In comparing September and October, the weather showcases a noticeable transition. September remains warm with average temperatures around 25°C (78°F) and highs reaching up to 35°C (94°F), while October cools down slightly, featuring an average of 21°C (69°F) and maximums of 33°C (91°F). Rainfall is more significant in September with 228 mm (9.0 in) over 15 days, compared to October's 120 mm (4.7 in) across just 9 days. Humidity levels remain relatively stable, dipping slightly from 84% in September to 83% in October, creating a pleasant change as the month progresses. For more detailed insights, you can check Unzen weather in October.
September and November exhibit distinctly different weather patterns. In September, temperatures range from a minimum of 16°C (62°F) to a maximum of 35°C (94°F), with an average temperature of 25°C (78°F). The month is also characterized by high humidity at 84% and significant precipitation, totaling 228 mm (9.0 in) over 15 rainy days. In contrast, November sees a noticeable drop in temperatures, with a minimum of 3°C (38°F) and a maximum of 25°C (78°F), yielding a cooler average of 15°C (59°F). Precipitation decreases significantly to 80 mm (3.1 in) over just 8 days, and humidity remains relatively high at 81%. For more insights into November weather, you can check Unzen weather in November.
September weather is characterized by warm temperatures, ranging from a minimum of 16°C (62°F) to a maximum of 35°C (94°F), with an average of 25°C (78°F). The month experiences significant rainfall, totaling 228 mm (9.0 in) over about 15 days, accompanied by high humidity levels at 84%. In contrast, December brings much cooler conditions, with temperatures dropping to a minimum of 0°C (33°F) and averaging 10°C (49°F), while the maximum reaches 24°C (76°F). Precipitation in December is much lighter, totaling 89 mm (3.5 in) over just 7 days, and humidity decreases slightly to 79%. For a more detailed look at how the weather varies, check out Unzen weather in December.
As September arrives in Unzen, the weather transitions to a unique blend of warmth and moisture that sets it apart from the preceding summer months. The average temperature remains comfortably warm, fluctuating between pleasant lows and higher daytime highs, while humidity levels reach a notable 84%, creating a lush, vibrant atmosphere. However, this month also introduces the rainy season, with significant precipitation over half the days, marking a stark contrast to the drier summer. This combination of heat and humidity enhances the region's stunning natural beauty, making September a captivating time to explore. For more detailed insights on Unzen's climate, visit Unzen Climate.