Last updated: August 21, 2025
Experience the vibrant September weather in Okayama, Japan, where temperatures fluctuate from a comfortable average of 25°C (77°F) to a scorching maximum of 36°C (97°F). As summer transitions to autumn, the month faces 12 days of rainfall, totaling 203 mm (8.0 in), contributing to a high humidity level of 87%. Embrace the blend of warm days and refreshing rain, perfect for exploring the region’s rich culture and stunning landscapes.
In September, Okayama experiences a delightful transition as it gently shifts from the sweltering heat of summer to more moderate temperatures. With minimums at 12°C (54°F) and average highs reaching 36°C (97°F), the month offers warm days that beckon outdoor exploration. The average temperature settles around 25°C (77°F), providing a comfortable backdrop for enjoying the vibrant landscapes, as the scorching July and August heat begins to recede. This month marks a significant drop from the previous extremes, making it an ideal time for visitors to experience the region's rich culture and natural beauty without the intensity of summer highs. Overall, September in Okayama serves as a reminder that the warmth of late summer can still be enjoyed in a pleasant, inviting climate.
In September, Okayama, Japan experiences a notable increase in precipitation, with 203 mm (8.0 in) recorded over 12 days of rain. This marks a continuation of the wet summer, following July's peak rainfall of 291 mm (11.5 in). While August sees a significant drop to 171 mm (6.7 in), September's precipitation further solidifies the region's transition into the autumn season. The increased rainfall during this month is crucial, as it replenishes local water sources and supports the lush landscapes that characterize Okayama. As the year progresses, it's evident that September serves as a pivotal time in the rainfall pattern, bridging the gap between the heavy summer rains and the lighter showers typical in the following months.
In September, Okayama experiences a notable humidity level of 87%, marking a slight decrease from the peak summer months of July and August, which hover at an elevated 92%. This gradual decline signals the transition into autumn, as the intense heat begins to recede. Interestingly, September's humidity is still higher than the year's earlier months, such as March and April, which see levels drop to the mid-70s. As summer gives way to fall, the humidity in Okayama remains relatively high, but it sets the stage for more comfortable conditions ahead, with October and November also showcasing lower humidity averages. This pattern highlights a seasonal rhythm where the sweltering summer air gives way to a refreshing autumn breeze, appealing to those who prefer milder weather.
In September, Okayama experiences a UV Index of 10, categorizing it as very high and indicating a burn time of just 15 minutes. This marks a slight decline from the peak levels seen in July and August, where the UV Index reached its highest at 12, representing a consistent pattern of extreme exposure during the summer months. As autumn approaches, residents and visitors alike should remain vigilant about sun protection, with the UV Index steadily decreasing to 7 in October. This trend highlights the importance of adapting to changing UV levels throughout the year. For detailed insights and safety measures, visit Okayama UV Index.
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September in Okayama, Japan, brings a delightful balance of sunlight, basking in 247 hours of radiant glow. As summer transitions into autumn, the sun remains generous, though slightly less intense than the peak of 302 hours in August. The month continues a trend of increasing daylight from the winter's 175 hours in January, reflecting a gradual buildup that reaches its zenith in the vibrant blooms of May. With each passing month, the hours of sunshine exemplify the region’s shift toward cooler weather, yet September stands out as a lovely sweet spot, where warmth and light still linger before the arrival of fall's more subdued embrace.
September in Okayama, Japan, marks a subtle transition in weather patterns, with a 33% chance of sunny days. While this is a slight uptick from the summer months of June and July, which each see a 26% chance of sun, it falls short of the sunnier footholds of early autumn, where October and November boast a more promising 56% likelihood. This trend suggests that while September may still deliver some bright days, the region is gradually moving towards a cooler, cloudier season as summer wanes, creating a delightful mix of both lingering warmth and early fall charm.
As September rolls in Okayama, Japan, the daylight duration begins a gentle decline, offering 12 hours of sunlight—a slight reduction from the summer peak of 14 hours in June and July. This month serves as a transition towards the shorter days of autumn, with daylight gradually waning as October approaches, bringing just 11 hours of brightness. The previous months showcased a vibrant increase in daylight, peaking in summer, and the shift in September marks a harmonious blend of lingering warmth with the early hints of fall. As the days grow shorter, one can appreciate the rhythmic change of seasons, each bringing its unique charm to Okayama’s landscape.
In September, the wind in Okayama, Japan, transitions into a gentle lull, with an average speed of 2.4 m/s (5 mph). This marks a slight dip compared to the summer months, where the breeze barely grazed the heat with 2.5 m/s (6 mph) in August. Following the trend of decreasing wind speeds from the peak summer months, September's soft winds offer a refreshing shift, heralding the approach of autumn. As the year progresses, a gradual increase in wind speeds returns in October and November, suggesting a subtle buildup of energy as the seasons change. Overall, September's mild air provides a serene backdrop for those enjoying the natural beauty of Okayama during this transitional month.
Weather in Okayama varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Okayama, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present two distinctly different weather experiences. In September, temperatures range from a mild 12°C (54°F) at night to a sizzling max of 36°C (97°F) during the day, coupled with high humidity at 87% and significant rainfall totaling 203 mm (8.0 in) over 12 days. This creates a warm and often humid atmosphere as summer transitions into autumn. In contrast, January experiences much cooler temperatures, with nighttime lows dropping to -3°C (26°F) and daytime highs peaking at 16°C (62°F). The month is characterized by minimal precipitation, averaging just 33 mm (1.3 in) over only 3 days, alongside a slightly lower humidity of 82%. For more detailed insights on January weather, you can refer to this link: Okayama weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures soar with a minimum of 12°C (54°F) and an average of 25°C (77°F), peaking at a sweltering 36°C (97°F). The month also sees significant rainfall, with 203 mm (8.0 in) spread over 12 days, accompanied by high humidity levels at 87%. In contrast, February is much cooler, featuring temperatures that range from a minimum of -5°C (23°F) to a maximum of 21°C (70°F), with an average of only 6°C (43°F). Precipitation is considerably less during this month, totaling just 47 mm (1.9 in) over 5 days, and humidity is relatively mild at 79%. For more details about February weather in Okayama, you can visit Okayama weather in February.
September and March present contrasting weather patterns. In September, temperatures soar with a minimum of 12°C (54°F) and an average high reaching up to 36°C (97°F), creating a warm and often humid atmosphere, with an average humidity of 87%. The month also experiences significant rainfall, totaling 203 mm (8.0 in) over about 12 days.
In contrast, March offers a much cooler climate, with temperatures ranging from a chilly -2°C (29°F) at night to a pleasant maximum of 24°C (75°F) during the day. Precipitation is lower, at 94 mm (3.7 in) spread over 9 days, and the humidity is also more moderate at 73%. For more details on the weather specifics, you can check out Okayama weather in March.
September and April present distinct contrasts in weather patterns. In September, temperatures range from a mild 12°C (54°F) at their lowest to a scorching maximum of 36°C (97°F), with an average temperature of 25°C (77°F). The month is characterized by high humidity at 87% and significant rainfall, totaling 203 mm over 12 days. In contrast, April offers a cooler climate, with temperatures dipping to a minimum of 1°C (34°F) and reaching a maximum of 26°C (79°F), averaging at 15°C (59°F). Precipitation is lower in April, with 119 mm falling over just 8 days and humidity is noticeably less at 74%. For a detailed overview of April's weather in Okayama, you can visit Okayama weather in April.
In September, the weather tends to be warmer and more humid compared to May, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 36°C (97°F). This month also experiences higher precipitation levels, with around 203 mm (8.0 in) falling over 12 days, resulting in increased humidity at 87%. Conversely, May has cooler temperatures, with a minimum of 7°C (45°F) and a maximum of 32°C (89°F), along with lower precipitation of 114 mm (4.5 in) over just 9 days and a humidity level of 84%. For more detailed insights into May weather conditions, you can check Okayama weather in May.
In comparing September and June weather, September typically showcases higher average temperatures, reaching up to an average of 25°C (77°F) with maximums soaring as high as 36°C (97°F). In contrast, June has a slightly cooler average temperature of 23°C (74°F) and peaks at 33°C (91°F). Both months experience a similar number of rainy days, with September receiving slightly more precipitation at 203 mm (8.0 in) compared to June’s 153 mm (6.0 in). Humidity levels are quite comparable as well, with September at 87% and June at 86%. For more specific details on June weather in Okayama, you can refer to Okayama weather in June.
When comparing the weather in September and July, September experiences a broader range of temperatures, with a minimum of 12°C and a maximum of 36°C, averaging around 25°C. In contrast, July tends to be warmer overall, with minimum temperatures starting at 20°C and maximums reaching 37°C, averaging 27°C. Furthermore, July is also marked by higher precipitation, totaling 291 mm over 17 days, making it wetter than September, which records 203 mm over 12 days. Humidity levels are slightly lower in September at 87%, compared to 92% in July. For more details on July weather, you can visit Okayama weather in July.
In comparing the weather of September and August, September tends to be slightly cooler, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 36°C (97°F), compared to August, which sees higher averages with a minimum of 18°C (65°F) and a maximum of 37°C (99°F). While August is characterized by a slightly lower average precipitation (171 mm or 6.7 in over 11 days) than September, which receives 203 mm (8.0 in over 12 days), both months feature high humidity levels, with August reaching 92% and September at 87%. For more details, you can check Okayama weather in August.
September weather is characterized by warmer temperatures, with averages around 25°C (77°F) and maximum readings reaching up to 36°C (97°F). In contrast, October brings a noticeable drop in temperature, with averages falling to 19°C (67°F) and maximums capping at 32°C (90°F). While both months experience significant rainfall, September sees more precipitation at 203 mm (8.0 in) over 12 days compared to October's 169 mm (6.7 in) across just 11 days. Humidity levels remain relatively close, with September at 87% and October at 85%. To learn more about the specifics of October weather, check out Okayama weather in October.
September and November showcase a striking contrast in weather conditions. September boasts warm temperatures, with a minimum of 12°C (54°F) and an average high reaching up to 36°C (97°F), accompanied by significant rainfall totaling 203 mm (8.0 in) across 12 days. The humidity remains high at 87%, contributing to the warm and often muggy atmosphere. In contrast, November is much cooler, with temperatures dipping to a minimum of 0°C (32°F) and averaging around 13°C (55°F). Precipitation is considerably lower, at just 30 mm (1.2 in) over 3 days, and humidity slightly decreases to 84%. For a more detailed look at November weather specifics, check out Okayama weather in November.
September and December present starkly contrasting weather conditions. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 36°C (97°F), with an average of 25°C (77°F). This month experiences a considerable amount of rain, totaling 203 mm (8.0 in) over 12 days, accompanied by high humidity levels at 87%. In contrast, December brings a significant drop in temperatures, with a minimum of -2°C (29°F) and a maximum of 20°C (69°F), resulting in a cooler average of 8°C (46°F). Precipitation decreases to 45 mm (1.8 in) spread over just 6 days, while humidity slightly lowers to 82%. For more insights into December weather, you can visit Okayama weather in December.
As September rolls in, Okayama experiences a noticeable shift in weather, blending the lingering warmth of summer with the onset of autumn. While the month can still see temperatures soaring up to 36°C (97°F) during the day, average temperatures settle comfortably around 25°C (77°F), offering a more pleasant climate compared to the peak summer heat. The humidity remains relatively high at 87%, contributing to a sense of mugginess, particularly during the frequent rain showers—12 days on average—leading to a total precipitation of 203 mm (8.0 in). This contrast in September not only marks a transition but also enhances the beauty of the region, making it a unique time to experience the lush landscapes. For a detailed understanding of weather trends throughout the year, visit Okayama Climate.