Last updated: August 21, 2025
In September, Setouchi, Japan experiences a delightful blend of warm temperatures and occasional rain, making it a unique month for visitors. The maximum temperature reaches up to 31°C (89°F), while the average sits comfortably at 24°C (76°F), providing a pleasant atmosphere for outdoor exploration. Nights cool down to a minimum of 17°C (64°F), inviting cozy evenings. However, the month is also marked by high humidity levels at 87%, contributing to the overall lushness of the region. With a total precipitation of 222 mm (8.7 in) spread over 13 days, travelers should be prepared for the occasional shower, which enhances the area's vibrant landscapes and rich cultural experiences.
September in Setouchi, Japan, marks a delightful transition as summer begins to fade. With minimum temperatures around 17°C (64°F) and averages rising to 24°C (76°F), the month's warmth lingers, offering pleasant days before autumn's chill sets in. The maximum temperatures peak at a comfortable 31°C (89°F), making it one of the last opportunities to enjoy outdoor activities in the sun. This month serves as a bridge from the heat of July and August, gradually retreating into cooler October, where temperatures drop significantly. Overall, September presents a harmonious blend of warmth and mildness, perfect for experiencing the natural beauty and vibrant festivals of the Setouchi region.
September in Setouchi, Japan, marks a notable spike in precipitation, with rainfall reaching 222 mm (8.7 in) over 13 days. This is a significant increase from the preceding months, showcasing a transition into the wetter period of the year. While summer's earlier deluge in July, with 303 mm (11.9 in), sets a high bar, September's consistent rainfall contributes to the region's lush landscapes as nature prepares for autumn. The month closely follows August's 173 mm (6.8 in), indicating a pattern of heightened precipitation that typically washes the area in vibrant hues, reflecting the beautiful interplay between seasonal shifts and climatic rhythms.
In September, the humidity in Setouchi, Japan stands at a notable 87%, reflecting a slight decline from the peak of 92% experienced in the preceding months of July and August. This drop marks a transition from summer’s intense moisture, yet the humidity remains relatively high, especially compared to the cooler months ahead. As the seasons shift, humidity levels gradually decrease from the summer highs, with October projected to bring a further reduction to 85%. Overall, the September climate captures the tail end of summer's lushness, paving the way for the more temperate conditions of autumn.
As summer transitions into autumn, September in Setouchi, Japan, presents a noteworthy UV Index of 10, placing it in the very high exposure category with a burn time of just 15 minutes. This slight decrease from the intense peak of 12 in July indicates that while the risk remains elevated, it is somewhat more manageable. The preceding months show a trend of extreme UV levels, with April to August consistently showcasing indices at 11 or higher. Following the summer months, September marks a gradual decline in UV radiation, paving the way for a moderate October ahead. It’s essential to remain vigilant about sun protection during this time, especially when engaging in outdoor activities. For detailed UV insights throughout the year, explore the Setouchi UV Index.
UV Risk Categories
As September settles in Setouchi, Japan, the region enjoys a delightful 248 hours of sunshine, a slight dip compared to the vibrant 306 hours of August, yet still basking in a generous amount of daylight. This month marks a transition as summer fades, with sunshine hours gradually decreasing from the peak summer months. Notably, September's sunlit days follow a steady rise that began in January with 177 hours, showcasing the region's delightful progression towards longer days in spring and summer. As October approaches with its 239 hours, the lingering warmth of September serves as a gentle reminder of the summer's brilliant glow, making it an ideal time to explore Setouchi's stunning coastal beauty.
As September rolls into Setouchi, Japan, the chance of sunny weather stands at 33%, marking a slight upswing compared to the summer months, where sunshine chances dip to around 29% and 31% in July and August, respectively. This subtle increase reflects a transition as the region shifts from the humid summer heat towards the milder and clearer days of autumn. Although still lower than the clear skies frequently enjoyed in October(57%) and November(56%), September offers a hopeful promise of sunny days, making it an alluring time for outdoor adventures amidst the scenic beauty of the Setouchi coastline. So, while the sun might not shine as brightly as it does in later months, it still invites opportunities for exploration under a soft, warming glow.
In Setouchi, Japan, September marks a transition as daylight decreases to 12 hours, a subtle shift from the longer summer days. Following the peak of 14 hours in both June and July, the daylight duration begins its gradual descent, hinting at the approaching autumn months. As the year progresses, daylight gradually shortens, from 13 hours in August to 11 hours in October. This consistent rhythm of changing light reflects the seasonal cycle, offering residents a beautiful blend of warm late-summer evenings and the softening glow of early autumn. The lengths of daylight in Setouchi not only delineate the seasons but also enrich the region's natural beauty throughout the year.
As summer transitions to autumn, September in Setouchi, Japan, greets visitors with a gentle breeze averaging 3.6 m/s (8 mph). This marks a slight uptick from the lazy winds of the summer months, peaking at 2.9 m/s (6 mph) in July. Following the peak summer heat, September's winds usher in a refreshing change, providing a subtle backdrop to the vibrant colors of the changing leaves. The rhythm of the wind continues to build, hinting at the more robust gusts of October and November, which reach 3.7 m/s (8 mph) and 4.3 m/s (10 mph) respectively. Overall, September captures that perfect blend of warmth and coolness, making it a delightful time to savor the serene beauty of Setouchi's landscapes.
Weather in Setouchi varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Setouchi, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly different weather patterns. In September, temperatures range from a mild 17°C (64°F) at night to a warm 31°C (89°F) during the day, accompanied by significant rainfall of 222 mm (8.7 in) over 13 days and high humidity at 87%. In contrast, January brings much colder conditions, with temperatures dropping to a minimum of -2°C (29°F) and peaking at only 14°C (57°F). Precipitation is minimal during this month, totaling just 39 mm (1.5 in) over 5 days, and humidity is slightly lower at 82%. For more information, you can explore Setouchi weather in January.
Comparing the weather in September and February reveals a stark contrast in temperatures and overall climate conditions. In September, temperatures range from a mild 17°C (64°F) to a warm 31°C (89°F), accompanied by high humidity at 87% and considerable precipitation of 222 mm (8.7 in) over 13 days. This creates a humid and often rainy atmosphere. In sharp contrast, February experiences much cooler temperatures, with a minimum of -3°C (28°F) and a maximum of 15°C (60°F), along with lower precipitation levels of 55 mm (2.2 in) spread over just 6 days. The humidity is also lower at 79%, contributing to a crisper winter feel. For more detailed information, you can check Setouchi weather in February.
September and March present markedly different weather patterns, reflecting the transition from summer to autumn and winter to spring, respectively. In September, temperatures range from a minimum of 17°C (64°F) to a maximum of 31°C (89°F), with an average of 24°C (76°F), alongside high humidity levels of 87%. This month also experiences substantial rainfall, with 222 mm (8.7 in) over approximately 13 days. In contrast, March sees much cooler conditions, with temperatures ranging from a low of 3°C (37°F) to a high of 18°C (64°F) and an average temperature of only 9°C (49°F). Precipitation is lighter in March at 108 mm (4.2 in) spread over 10 days, and humidity is lower at 73%. For more detailed information, you can explore Setouchi weather in March.
The weather in September is noticeably warmer and more humid compared to April. With temperatures ranging from a minimum of 17°C (64°F) to a maximum of 31°C (89°F), September averages around 24°C (76°F), while April experiences a cooler climate with temperatures between 4°C (40°F) and 21°C (71°F), averaging just 13°C (56°F). Moreover, September sees significantly more rainfall, accumulating 222 mm (8.7 in) over 13 days, in contrast to April's 130 mm (5.1 in) over 9 days. The humidity levels also peak in September at 87%, compared to 74% in April, making the former feel considerably more oppressive. For more detailed insights on April conditions, you can explore Setouchi weather in April.
September and May exhibit notable differences in weather patterns. September tends to be warmer, with average temperatures ranging from a minimum of 17°C (64°F) to a maximum of 31°C (89°F), while May is cooler, averaging between 10°C (50°F) and 25°C (77°F). Additionally, September experiences significantly more rainfall, with 222 mm (8.7 in) of precipitation over 13 days compared to May's 131 mm (5.2 in) over just 9 days. Humidity levels are also slightly higher in September at 87%, compared to May's 84%. For more details, visit Setouchi weather in May.
In comparing the weather of September and June, September tends to be warmer, with average temperatures reaching 24°C (76°F) and maximums soaring up to 31°C (89°F). In contrast, June is slightly cooler, with averages of 22°C (71°F) and maximums hitting 27°C (80°F). Both months experience significant rainfall, but September sees more precipitation at 222 mm (8.7 in) over 13 days, compared to June's 164 mm (6.5 in) across 12 days. Humidity levels are similar, with September at 87% and June at 86%. For a closer look at the specific weather patterns, you can visit Setouchi weather in June.
In comparing the weather between September and July, it's evident that July tends to be slightly warmer, with average temperatures reaching 26°C (78°F) compared to 24°C (76°F) in September. The maximum temperature also peaks higher in July at 32°C (91°F) versus 31°C (89°F) in September. However, September experiences more rainfall, with 222 mm (8.7 in) over 13 days, while July sees a heftier 303 mm (11.9 in) across 16 days. Humidity levels are marginally lower in September at 87%, compared to 92% in July. For a more detailed look at July weather, you can refer to Setouchi weather in July.
In comparing the weather of September and August, we see a notable shift in temperatures and precipitation levels. September generally experiences milder temperatures, with average highs of 31°C (89°F) compared to August's maximum of 32°C (91°F). The minimum temperature also drops in September to 17°C (64°F), while August starts at a warmer 21°C (69°F). Additionally, September features higher precipitation, totaling 222 mm (8.7 in) over 13 days, compared to August's 173 mm (6.8 in) over 12 days. Humidity remains relatively high in both months, though slightly lower in September at 87% compared to August's 92%. For more detailed insights on August weather, you can check Setouchi weather in August.
September typically experiences warmer temperatures compared to October, with daily averages reaching about 24°C (76°F) and maximums peaking at 31°C (89°F). In contrast, October sees a drop in temperatures, averaging 19°C (67°F) with highs around 27°C (82°F). Precipitation levels are relatively similar, with September recording 222 mm (8.7 in) over 13 days and October slightly less at 211 mm (8.3 in) across 11 days. Humidity remains high in both months, but it is marginally lower in October at 85%, compared to 87% in September. For more detailed insights on October weather, you can visit Setouchi weather in October.
September tends to be much warmer and more humid than November, with average temperatures soaring to around 24°C (76°F) and highs reaching up to 31°C (89°F). In contrast, November sees a significant drop in temperature, with an average of just 14°C (57°F) and maximums around 22°C (71°F). September also experiences higher rainfall, with 222 mm (8.7 in) over 13 days, compared to a mere 38 mm (1.5 in) across 5 days in November, indicating a drier and cooler transition into late autumn. Overall, the weather shifts dramatically from the warm, humid days of September to the crisp, mild conditions of November. For more information, you can check Setouchi weather in November.
In September, the weather is markedly warmer and more humid, with temperatures ranging from a minimum of 17°C (64°F) to a maximum of 31°C (89°F) and an average of 24°C (76°F). The month also experiences significant rainfall, totaling 222 mm (8.7 in) over 13 days, contributing to a high humidity level of 87%. In contrast, December brings a dramatic drop in temperature, where the minimum temperature falls to 1°C (33°F) and the maximum reaches only 19°C (66°F), with an average of 9°C (48°F). Precipitation decreases significantly to 52 mm (2.0 in) spread over just 6 days, and humidity drops slightly to 82%. For those interested in more detailed insights into December weather, you can visit Setouchi weather in December.
As summer gently transitions into autumn, September in Setouchi brings a refreshing change, with temperatures cooling down and the vibrant landscape preparing for fall. Unlike the sweltering heat of July and August, September offers a more comfortable climate with significantly lower maximum temperatures and a notable increase in humidity. This month also sees an uptick in rainfall, with frequent downpours that nourish the region's lush foliage. If you're considering visiting, expect warm days infused with the scent of rain-soaked earth, making it a unique time to experience Setouchi’s natural beauty. For more details on the local climate variations throughout the year, visit Setouchi Climate.