Last updated: August 21, 2025
September in Kusatsu, Japan presents a captivating blend of mild temperatures and significant rainfall, ideal for those who appreciate lush landscapes. With maximum temperatures peaking at 29°C (85°F) and an average of 19°C (66°F), the month offers comfortable days. However, a minimum of 7°C (44°F) at night suggests cooler evenings—perfect for cozy gatherings. The town experiences 168 mm (6.6 in) of rain over approximately 19 days, contributing to its vibrant greenery. Coupled with humidity levels reaching 89%, September's climate is immersive and invigorating, inviting visitors to explore Kusatsu's renowned hot springs and scenic beauty.
As summer fades into autumn, Kusatsu, Japan, experiences a significant shift in temperatures throughout September. The month brings a gentle cooling trend, where nighttime temperatures dip to a refreshing 7°C (44°F), while daytime averages rise to a pleasant 19°C (66°F). With maxima reaching around 29°C (85°F), the climate remains comfortable for outdoor activities, making it an ideal time to explore the area's lush landscapes and hot springs. This transitional period is marked by diminishing humidity and clearer skies, encouraging visitors to savor the vibrant onset of fall, all while leaving behind the peak summer heat.
In September, Kusatsu experiences a notable shift in its precipitation patterns, with 168 mm (6.6 in) of rainfall over approximately 19 days. This amount mirrors the substantial rainfall of the preceding summer months, particularly July’s peak of 278 mm. The transition into autumn is marked by consistent rainfall as the weather cools, making September one of the wetter months alongside July and June. As temperatures begin to drop, the relatively high number of precipitation days indicates that residents and visitors can expect frequent showers, contributing to the lush greenery that characterizes this season in the region. The data highlights a smooth continuation of the wet conditions leading into the autumn, setting the stage for the dramatic change in scenery that follows.
In September, Kusatsu, Japan, experiences a significant dip in humidity levels compared to the sweltering summer months, with an average humidity of 89%. This slight decrease follows a peak in July and August, when humidity levels soared to 92%, creating a muggy atmosphere typical of the rainy season. As the transition into autumn begins, humidity gradually recedes, reflecting the region's shift toward cooler temperatures. This trend, characterized by consistently high humidity in early summer months and a gradual decline into fall, highlights Kusatsu's unique climatic rhythm, making the month of September a more palatable time to enjoy the lush, vibrant landscapes of this beautiful locale.
As September unfolds in Kusatsu, Japan, the UV Index stands at 10, marking it as a period of very high exposure with a burn time of just 15 minutes. This trend reflects a slight decrease from the peak extreme levels observed in the summer months of June through August, where the index consistently hit 11. With October on the horizon, the UV Index is expected to drop further to a high category of 7, encouraging sun-seekers to remain vigilant. September serves as a transition month, where the lingering summer sun still demands attention—especially for outdoor enthusiasts. To learn more about the UV Index throughout the year, check out Kusatsu UV Index.
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September in Kusatsu, Japan, welcomes 228 hours of sunshine, marking a gentle transition as summer begins to fade. This month continues the trend of bright days, albeit slightly less than the vibrant summer peak of 287 hours in May and 278 hours in August. Interestingly, while autumn days bring a charming warmth, they are being gradually overshadowed by the cooler months ahead, as evidenced by the drop to 209 hours in October. Overall, September captures a delightful balance of lingering summer rays and the crisp anticipation of fall, making it a perfect time to enjoy the rich scenery and the natural thermal wonders for which Kusatsu is renowned.
In Kusatsu, Japan, the likelihood of sunny weather in September is relatively low, with only a 21% chance of sunshine. This trend reflects a common pattern as summer transitions into autumn, where the days grow shorter and cloud cover often increases. Interestingly, September shares this sunny probability with both August and July, which are typically seen as part of the summer season. Overall, the chance of sun tends to dip in the late summer and early autumn months, making the likelihood of encountering clear skies in September less promising compared to earlier months in the year, such as November, which boasts a much higher 46% chance of sunshine. As such, visitors to Kusatsu should prepare for a mix of weather conditions if they plan to explore this beautiful region in the early fall.
As summer wanes in Kusatsu, Japan, September marks a gentle transition in daylight duration, with the sun gracing the skies for 12 hours each day. Following the peak of 14 hours in June and July, the soft decline continues into autumn, reflecting a gradual yet consistent reduction in daylight. The shift from August's 13 hours to September's 12 hours signals the approach of the cozy, cooler months ahead. This rhythmic change showcases the beautiful ebb and flow of nature, inviting residents and visitors alike to revel in the warm hues of early fall while they still can. As October approaches, daylight will soon settle to 11 hours, but for now, September offers a perfect balance between summer's warmth and autumn's embrace.
As September arrives in Kusatsu, Japan, the gentle whispers of the wind begin to break the summer's calm. With an average wind speed of 1.7 m/s (4 mph), the breezes in this month reflect a subtle transition towards autumn. Notably, September's winds are slightly stronger than those of the previous summer months, suggesting a gradual rejuvenation in the air. This trend continues into October and November, where the wind speed incrementally rises, hinting at the onset of cooler weather and a vibrant seasonal change. The winds in Kusatsu tell a tale of nature’s rhythm, reminding us that as the year wanes, each gust carries hints of the beauty to come.
Weather in Kusatsu varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Kusatsu, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present starkly contrasting weather patterns. In September, temperatures range from a minimum of 7°C (44°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F), making it a warm and humid month with 89% humidity and significant rainfall of 168 mm (6.6 in) over 19 days. In contrast, January experiences much colder temperatures, with a minimum of -12°C (11°F) and a maximum of 9°C (49°F), averaging -2°C (29°F). The month is drier, receiving only 74 mm (2.9 in) of precipitation across 16 days, while maintaining a similar humidity level of 88%. For more detailed insights on January conditions, check out Kusatsu weather in January.
September and February present strikingly contrasting weather conditions. In September, temperatures range from a minimum of 7°C (44°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F). This month experiences significant precipitation, totaling 168 mm (6.6 in) over 19 days, coupled with a high humidity level of 89%. In sharp contrast, February brings much colder temperatures, with a minimum of -11°C (12°F) and a maximum of 17°C (63°F), averaging -1°C (31°F). Precipitation is lower in February at 74 mm (2.9 in) across 14 days, and humidity remains slightly lower at 86%. For more detailed information on the winter conditions in Kusatsu, you can refer to Kusatsu weather in February.
September and March present contrasting weather patterns, highlighting the transition from summer to autumn compared to the onset of spring. In September, temperatures range from a mild 19°C (66°F) average to a warm maximum of 29°C (85°F), with relatively high humidity at 89% and frequent rainfall totaling 168 mm over 19 days. In contrast, March is much cooler, with an average temperature of only 4°C (39°F) and night-time lows dipping as low as -8°C (19°F). While it experiences less precipitation at 111 mm over 14 days, the humidity is also lower, at 81%. To explore March weather in greater detail, you can check out Kusatsu weather in March.
September and April present distinctly different weather experiences. In September, temperatures range from a minimum of 7°C (44°F) to a maximum of 29°C (85°F), with an average temperature of 19°C (66°F). This month sees considerable rainfall, totaling 168 mm (6.6 in) over 19 days, and a high humidity level at 89%. In contrast, April features cooler temperatures, with a minimum of -5°C (24°F) and a maximum of 27°C (81°F), averaging 9°C (48°F). Precipitation in April is lower at 112 mm (4.4 in) over 15 days, and humidity is also reduced to 78%. For a more detailed look at April weather, you can visit Kusatsu weather in April.
In comparing the weather between September and May, there are noticeable differences in temperature and precipitation. September experiences milder temperatures, with an average of 19°C (66°F) and highs reaching 29°C (85°F), while May has a lower average of 15°C (59°F) with similar maximum temperatures of 30°C (87°F). Additionally, September is characterized by higher humidity levels at 89%, compared to May's more comfortable 81%. Precipitation is also slightly heavier in September, with 168 mm (6.6 in) over 19 days, whereas May sees 139 mm (5.5 in) across 16 days. For more detailed insights on the weather during this month, you can check out Kusatsu weather in May.
In comparing the weather between September and June, we see some similarities and slight variations. Both months experience an average temperature around 18-19°C (64-66°F), with June being marginally cooler with a minimum temperature of 6°C (43°F) compared to September's 7°C (44°F). Interestingly, both months record the same amount of precipitation, at 168 mm (6.6 in), yet September sees rain for one additional day, totaling 19 days of precipitation versus June's 18 days. Humidity levels are also quite similar, with September slightly higher at 89% compared to June at 88%. To explore more about June weather in Kusatsu, you can check Kusatsu weather in June.
When comparing the weather between September and July, notable differences emerge in both temperature and precipitation. September experiences milder temperatures, with a minimum of 7°C (44°F) and an average of 19°C (66°F), while July is significantly warmer, with a minimum of 14°C (58°F) and an average of 22°C (72°F). The maximum temperatures in July can reach up to 33°C (91°F), whereas September peaks at 29°C (85°F). Additionally, July is characterized by higher precipitation, receiving 278 mm (10.9 in) over 25 days, compared to September's 168 mm (6.6 in) across 19 days. Humidity levels remain relatively high in both months, with July at 92% and September slightly lower at 89%. For more details on July weather patterns, you can refer to Kusatsu weather in July.
In comparing the weather of September and August, September experiences cooler temperatures with a minimum of 7°C (44°F) and a maximum of 29°C (85°F), unlike August, which has a higher minimum of 11°C (52°F) and can soar up to 34°C (93°F). The average temperature in September is also lower at 19°C (66°F) compared to August's average of 23°C (74°F). While both months see significant rainfall, September has precipitation of 168 mm (6.6 in) over 19 days, just slightly less than August's 177 mm (7.0 in) over 22 days. Humidity levels are fairly high in both months, with September at 89% and August at 92%. For a detailed look at August weather patterns, you can visit Kusatsu weather in August.
September generally offers warmer temperatures, with averages around 19°C (66°F) and maxing out at 29°C (85°F), while October sees a notable drop, with an average of 13°C (55°F) and a maximum of 26°C (80°F). Although October's minimum temperature can dip to 1°C (34°F), making it feel considerably cooler, it remains mostly comfortable compared to the overall chill of late autumn. Precipitation is slightly higher in October, with 217 mm (8.5 in) over 17 days, compared to September's 168 mm (6.6 in) over 19 days, but the humidity remains fairly similar at 87% for October and 89% for September. For more detailed insights, check out Kusatsu weather in October.
September and November present a stark contrast in weather conditions. In September, temperatures range from a minimum of 7°C (44°F) to a maximum of 29°C (85°F), with an average of 19°C (66°F). This month typically experiences high humidity at 89% and frequent rainfall, totaling 168 mm (6.6 in) over 19 days. In contrast, November cools significantly, with temperatures dropping to a minimum of -4°C (24°F) and averaging 7°C (44°F), while the maximum only reaches 20°C (68°F). Rainfall in November is notably lower, at 50 mm (2.0 in) across 10 days, accompanied by slightly lower humidity at 85%. This marked change reflects the transition from the warmer, wetter late summer to the cooler, drier fall season. For more details on November weather in Kusatsu, visit Kusatsu weather in November.
September and December present quite contrasting weather conditions. In September, temperatures range from a mild 7°C (44°F) to a warm 29°C (85°F), with an average of 19°C (66°F). The month experiences significant rainfall, with 168 mm (6.6 in) of precipitation spread over 19 days, leading to a high humidity of 89%. In contrast, December brings much colder temperatures, with a minimum of -8°C (17°F) and an average temperature of only 1°C (35°F). The maximum temperature in December peaks at 18°C (65°F). Despite lower precipitation levels of 76 mm (3.0 in) occurring on 15 days, the humidity remains relatively high at 86%. For more detailed information about December weather, you can visit Kusatsu weather in December.
As September unfolds in Kusatsu, the transition to fall is evident, marked by a cooling atmosphere that presents a refreshing contrast to the summer heat. While temperatures can still peak at a mild 29°C, the drop in average highs to around 19°C invites a more comfortable outdoor experience. Frequent rainfall, with 19 wet days contributing to a significant total precipitation of 168 mm, underscores the seasonal shift, while the high humidity at 89% can add to the cozy yet damp feeling in the air. Compared to the scorching summer months, September offers a unique blend of lingering warmth and the crispness of early autumn, making it a delightful time to explore the lush landscapes of Kusatsu. For more insights on the region's climate, visit Kusatsu Climate.