Last updated: August 21, 2025
In September, Minamiuonuma, Japan, experiences a dynamic range of weather conditions. With a maximum temperature reaching 31°C (89°F) and an average temperature of 19°C (67°F), the month showcases the warmth of late summer transitioning into early autumn. However, temperatures can dip to a minimum of 6°C (43°F), highlighting the variability of the season. Rainfall is significant, accumulating 223 mm (8.8 in) across 19 days, resulting in a high humidity level of 89%. This combination of warmth and moisture shapes a rich, lush environment, making September a vibrant time to explore the natural beauty of the region.
In September, Minamiuonuma, Japan experiences a delightful transition as summer dwindles into autumn. The temperatures range from a comfortable 6°C (43°F) in the early mornings to a warm 31°C (89°F) during the day, presenting an inviting mix of cool and warm weather. With an average temperature of 19°C (67°F), this month signifies more than just a shift; it marks the gradual cooling that leads into the crisp air of fall. As the summer heat begins to recede, the pleasant days are perfect for outdoor activities, making September a beautifully balanced month in this enchanting region.
In September, Minamiuonuma experiences a notable precipitation total of 223 mm (8.8 in), characterized by 19 rainy days. This marks a slight decrease from the heavier rainfall of July and August, yet it remains significant for the month. The precipitation amount typically reflects the transitions in weather patterns as autumn approaches, contributing to the lush landscapes that the region is renowned for. While the rainfall is less intense compared to the summer months, the steady frequency of rainfall days suggests a persistent, if gentler, moisture presence that continues to nourish the environment as it shifts into cooler temperatures. Overall, September serves as a bridge, where the effects of summer storms gradually give way to the serene, crisp essence of fall.
In September, Minamiuonuma experiences a humidity level of 89%, which signifies a slight drop from the sweltering heights of 92% in both July and August. This gradual decrease marks a shift as summer gives way to autumn, creating a more comfortable atmosphere for residents and visitors alike. The lingering high humidity, characteristic of the summer months, still influences the early fall, maintaining a rich, verdant landscape. Notably, September's humidity aligns closely with the 88% recorded in June, highlighting a transition while retaining a semblance of the summer's warmth. As the year progresses towards October, the humidity levels continue to remain relatively high, indicative of Minamiuonuma's consistently moist climate year-round.
As summer gives way to autumn in September, Minamiuonuma experiences a dip in UV intensity, but it still registers a notable UV Index of 9, classifying exposure as very high. This means that while the burn time is extended to 15 minutes, caution is still necessary for outdoor activities. Following the peak summer months, where the UV Index soared to 11, September illustrates a gradual decline, hinting at a shift in seasonal weather patterns. As we transition towards the cooler months, it’s essential to remain vigilant about sun protection and adjust accordingly. For more information on the UV Index throughout the year, check out Minamiuonuma UV Index.
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September in Minamiuonuma, Japan, embraces a delightful balance of sun and cool air, boasting 249 hours of sunshine. As summer's vibrancy wanes, the days become slightly shorter, yet this month still enjoys a healthy amount of sunlight. Following the peak of 302 hours in May, sunshine gradually declines, with September positioned comfortably between the summer's brightness and the more subdued light of autumn. The trend reveals a gentle tapering off, hinting at nature's preparation for the crisp chill of October, which sees a further drop to 217 hours. This seamless transition not only enhances the beauty of September's landscapes but also invites locals and visitors alike to savor the fading warmth before winter's arrival.
In September, Minamiuonuma experiences a 26% chance of sunny weather, which reflects a slight uptick from the summer months of July and August, where the odds hover around 20-30%. This transitional period hints at a gradual shift towards more favorable weather conditions as autumn approaches. While September's sunshine is still not abundant, it stands out in contrast to the cooler, cloudier days that precede it in August. Looking at the broader trends, the likelihood of sunny days not only varies throughout the year but also suggests that fall brings a potential for clearer skies, with the following months of October and November showing even higher probabilities of sunshine at 32% and 40%, respectively. Thus, September serves as a bridge, where fleeting sunny moments can still be enjoyed amidst the seasonal changes.
As summer wanes, the daylight duration in Minamiuonuma, Japan, exhibits a gradual yet noticeable transition. September beckons with approximately 12 hours of daylight, a gentle decline from the peak 14 hours experienced in June, July, and August. This shift marks the beginning of autumn, showcasing a blend of lingering warmth and the early whispers of cooler months ahead. Following September, daylight continues to diminish to 11 hours in October, accentuating the rhythmic ebb and flow of the seasons. This pattern not only highlights the vibrant changes in nature but also sets the stage for cozy fall days ahead, inviting both reflection and nostalgia as the days grow shorter.
In September, the wind in Minamiuonuma exhibits a gentle yet refreshing character, with an average speed of 1.7 m/s (4 mph). Following the summer months, where lighter breezes prevailed, September brings a slight increase in wind, hinting at the transition into autumn. This trend of modest fluctuations is evident throughout the year, with average speeds peaking in the spring months and dipping during the hot summer. The cooler September air, accompanied by a mild breeze, creates an inviting atmosphere perfect for enjoying the region's stunning autumn foliage. As the seasons change, so too does the wind, subtly guiding the inhabitants and visitors through the picturesque landscapes of Japan’s mountainous terrain.
Weather in Minamiuonuma varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Minamiuonuma, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is characterized by significantly warmer temperatures, ranging from a minimum of 6°C (43°F) to a maximum of 31°C (89°F), with an average of 19°C (67°F). The month experiences considerable precipitation, totaling 223 mm (8.8 in) across 19 days, accompanied by high humidity at 89%. In contrast, January brings much colder conditions, with temperatures plunging to a minimum of -14°C (6°F) and only reaching a maximum of 8°C (47°F), resulting in an average temperature of -3°C (28°F). Although January sees slightly less precipitation at 199 mm (7.8 in) over 22 days, the humidity remains similar at 88%. For more detailed information about January weather, you can refer to Minamiuonuma weather in January.
When comparing the weather in September and February, we see striking contrasts. September offers a warm range of temperatures, with highs reaching up to 31°C (89°F) and an average of 19°C (67°F), while February experiences much colder conditions, with maximum temperatures only reaching 14°C (57°F) and averages around -2°C (29°F), plunging to a minimum of -19°C (-2°F). Additionally, September is characterized by significant rainfall, with 223 mm (8.8 in) over 19 days, while February sees slightly less precipitation at 185 mm (7.3 in) spread over 22 days. Humidity levels are also high in both months, with September at 89% and February at 86%. For more details, check out Minamiuonuma weather in February.
September and March present contrasting weather patterns. In September, temperatures range from a minimum of 6°C (43°F) to a maximum of 31°C (89°F), with an average of 19°C (67°F). The month is characterized by high humidity at 89% and significant rainfall, totaling 223 mm (8.8 in) over 19 days. Conversely, March experiences much cooler temperatures, with a minimum of -10°C (14°F) and a maximum of 20°C (68°F), averaging just 3°C (37°F). While March sees less total precipitation at 174 mm (6.9 in) over 20 days, the humidity is slightly lower at 81%. For a more detailed look at the weather in March, you can check Minamiuonuma weather in March.
In comparing the weather between September and April, there are notable differences in temperature and conditions. September boasts a much warmer average temperature of 19°C (67°F), with maximums reaching up to 31°C (89°F), while April experiences a cooler average of just 8°C (46°F) and a maximum temperature of 26°C (79°F). The precipitation levels are also distinct, with September receiving 223 mm (8.8 in) across 19 days, compared to April’s 167 mm (6.6 in) over 18 days. Additionally, September has a higher humidity level at 89%, while April's humidity is more moderate at 78%. For specific insights on April weather, you can check Minamiuonuma weather in April.
When comparing the weather in September and May, there are noticeable differences in temperature and precipitation. September experiences a wider temperature range, with minimums reaching 6°C (43°F) and maximums typically around 31°C (89°F). In contrast, May starts with cooler temperatures, with a minimum of 1°C (34°F) and an average of 15°C (58°F), while peaking at a maximum of 30°C (86°F). Precipitation levels are also noteworthy; September has more rain, averaging 223 mm (8.8 in) over 19 days, compared to May's 181 mm (7.1 in) over 16 days. The humidity is slightly higher in September at 89%, compared to 81% in May. For more detailed conditions, you can check Minamiuonuma weather in May.
When comparing the weather in September and June, both months exhibit relatively mild temperatures, with September featuring a slightly higher average of 19°C (67°F) compared to June's 18°C (64°F). The maximum temperatures are comparable as well, with September peaking at 31°C (89°F) and June reaching 30°C (86°F). However, September tends to be wetter, receiving 223 mm (8.8 in) of precipitation over 19 days, while June has a total of 201 mm (7.9 in) across 18 days. Both months also maintain high humidity levels, with September at 89% and June at 88%. For more specific insights about June weather, you can check out Minamiuonuma weather in June.
When comparing the weather in September and July, several notable differences emerge. September boasts a broader temperature range, with minimums dropping to 6°C (43°F) and maximums reaching up to 31°C (89°F), while the average temperature is around 19°C (67°F). In contrast, July is generally warmer, with minimums of 14°C (58°F) and maximums hitting 32°C (90°F), leading to a higher average of 22°C (73°F). Nonetheless, July experiences significantly more precipitation, accumulating 376 mm (14.8 in) over 24 days, compared to September's 223 mm (8.8 in) over 19 days. Humidity levels are also slightly higher in July at 92%, compared to 89% in September. For more detailed insights on July weather, you can check Minamiuonuma weather in July.
In comparing the weather of September to August, it becomes clear that September experiences cooler temperatures, with a minimum of 6°C (43°F) compared to August’s minimum of 10°C (50°F). The average temperature in September is 19°C (67°F), significantly lower than August's average of 24°C (75°F). Despite these cooler temperatures, September also sees a wide range with maximum temperatures reaching up to 31°C (89°F), just slightly cooler than August’s high of 33°C (91°F). Precipitation is fairly consistent, with September receiving 223 mm (8.8 in) over 19 days, compared to August’s 238 mm (9.4 in) over 22 days. Humidity remains high in both months, with September at 89% and August slightly higher at 92%. For more details on August's weather, visit Minamiuonuma weather in August.
September and October bring noticeable changes in weather characteristics. In September, temperatures range from a minimum of 6°C (43°F) to a maximum of 31°C (89°F), with an average of 19°C (67°F), alongside high humidity levels at 89%. The month experiences significant rainfall, with 223 mm (8.8 in) spread over 19 days. Conversely, October sees a drop in temperatures, featuring a minimum of 2°C (36°F) and a maximum of 27°C (81°F), leading to a cooler average of 13°C (56°F). Precipitation increases slightly to 256 mm (10.1 in), occurring on 18 days, while humidity remains relatively stable at 87%. For more detailed insights on the October weather, you can explore Minamiuonuma weather in October.
September and November present striking contrasts in weather. In September, temperatures range from a mild minimum of 6°C (43°F) to a warm maximum of 31°C (89°F), with an average of 19°C (67°F). This month also sees considerable rainfall, with 223 mm (8.8 in) of precipitation recorded over 19 days and a high humidity level of 89%.
In contrast, November ushers in cooler temperatures, with a minimum of -9°C (17°F) and an average of 6°C (44°F), peaking at 21°C (71°F). While precipitation is less frequent than in September, it still accounts for 145 mm (5.7 in) over 18 days, maintaining a relative humidity of 85%. For more detailed information, you can check out Minamiuonuma weather in November.
September and December present stark contrasts in weather conditions. In September, temperatures often range from a minimum of 6°C (43°F) to a warm maximum of 31°C (89°F), with an average of 19°C (67°F). The month sees significant precipitation at 223 mm (8.8 in) over 19 days, accompanied by high humidity levels at 89%. In contrast, December experiences much colder temperatures, with a minimum dipping to -14°C (7°F), an average of 0°C (32°F), and a maximum of 18°C (65°F). Although the precipitation in December is slightly higher at 226 mm (8.9 in) spread across 22 days, the humidity is marginally lower at 86%. For more detailed insights, you can visit Minamiuonuma weather in December.
As September rolls into Minamiuonuma, the weather experience shifts notably compared to the preceding summer months. With temperatures gradually easing into a more comfortable range, the maximum heat gives way to refreshing cooler days. However, this transition is accompanied by significant precipitation—a hallmark of early autumn, resulting in a higher number of rainy days. Humidity levels remain elevated, creating a lush, vibrant landscape, yet it can feel quite muggy at times. This blend of warmth and moisture cultivates a unique atmosphere that sets September apart, making it an intriguing time to explore the region. For a deeper look at year-round conditions, explore Minamiuonuma Climate.