Last updated: August 21, 2025
As September unfolds in Shimonoseki, Japan, the weather paints a vibrant picture of late summer transitioning into autumn. Average temperatures hover around a comfortable 24°C (76°F), with daily highs reaching up to 32°C (89°F) and dropping to a mild 18°C (65°F) at night. However, this month is characterized by notable humidity levels at 84%, creating a semi-tropical ambiance. Rainfall is also significant, accumulating to 226 mm (8.9 in) over approximately 12 days, emphasizing the need for a light jacket or umbrella. Overall, September offers a blend of warm days and occasional showers, reflecting the dynamic climate of this coastal city.
In September, Shimonoseki experiences a delightful transition from the sweltering summer months, with temperatures ranging from a comfortable 18°C (65°F) at night to a warm 32°C (89°F) during the day. The average temperature of 24°C (76°F) reflects the last vestiges of summer warmth, making it an ideal time for outdoor exploration and enjoying local festivals. As autumn approaches, the city begins to cool, yet the lingering warmth provides a perfect backdrop for experiencing the vibrant maritime culture that defines this coastal gem. Visitors can revel in the pleasant climate before the significant drop in temperatures that follows in October.
September in Shimonoseki, Japan, brings a significant amount of rainfall, with 226 mm (8.9 in) accumulating over an average of 12 days. This substantial precipitation marks the tail end of the summer season but continues to reflect the pattern established in the preceding months. After a particularly wet July and August, September's rainfall remains notable but begins to taper off compared to the peak summer months. This gradual decline in precipitation sets the stage for the cooler, drier autumn months ahead, as the city transitions from the intense heat and humidity of summer into a more temperate climate.
In September, Shimonoseki experiences a notable drop in humidity, averaging 84%, down from the sweltering 95% in July and 93% in August. This shift marks a transition from the peak summer mugginess, inviting a subtle sense of relief as autumn approaches. The humidity levels in September remain elevated compared to earlier months, such as April and March, yet they signal the beginning of a gradual decline leading into the cooler months. As the city navigates this seasonal change, the weather becomes more comfortable, making it an ideal time for outdoor activities before the chill of October sets in. Overall, September serves as a bridge between the heat of summer and the refreshing embrace of fall, showcasing Shimonoseki’s dynamic climate.
As summer fades into autumn, September in Shimonoseki, Japan, presents a transition in UV exposure, with a high UV Index of 10, categorized as very high. This marks a slight dip from the peak 12 recorded in the sweltering months of July and August, where the burn time shrank to just 10 minutes. Nonetheless, the need for sun protection remains crucial, as the 15-minute burn time in September underscores the heightened risk of skin damage. With October's UV Index expected to further decrease, this month serves as a gentle reminder of the waning summer sun, making it essential to stay vigilant while enjoying the outdoors. For more detailed insights, visit Shimonoseki UV Index.
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As September arrives in Shimonoseki, Japan, the warm embrace of summer begins to wane, yet the city still basks in a generous 256 hours of sunshine. This delightful month marks a transition from the peak brilliance of August, which boasts the highest sunlight at 305 hours, to the cooler days of autumn. While sunshine hours gradually decline through the autumn months, September’s glow is a radiant reminder of the waning summer, as it's still significantly brighter than the chillier winter months ahead. With October not far behind at 253 hours, it’s clear that Shimonoseki enjoys a vibrant tapestry of sunlight throughout the year, making each season uniquely captivating.
September in Shimonoseki, Japan, offers a 31% chance of sunny weather, making it one of the more moderate months for sun-seekers. Following the typically sun-drenched spring months of April (46%) and a slightly less bright May (34%), the summer sun begins to wane with July (24%) and August (27%), leading into the fall. Interestingly, the likelihood of sunshine increases significantly in October to 59%, suggesting that autumn brings more favorable weather conditions. This trend highlights September as a transitional month—though it presents a decent chance for sunny days, it's clear that those seeking plentiful sunshine may want to plan for later in the year.
As summer gives way to autumn, September in Shimonoseki, Japan, experiences a gentle decline in daylight, with 12 hours of sunlight illuminating the days. This marks a subtle shift from the 14 hours enjoyed in July and June, reflecting the seasonal transition. With daylight gradually shortening, September's hours serve as a bridge, leading to the crisp, shorter days of October and November. The change is part of a natural rhythm, where daylight gradually ebbs from the long, sun-filled days of summer to the cozier, twilight evenings of winter, creating a beautiful tapestry of shifting light throughout the year.
In September, Shimonoseki experiences a gentle shift in its wind patterns, with an average wind speed of 4.9 m/s (11 mph). This marks a slight increase from the calmer summer months of July and August, where winds hovered around 4.0 m/s and 4.5 m/s respectively. As autumn approaches, the winds gradually strengthen, hinting at the transition to the cooler months ahead. In contrast to earlier months, where wind speeds dipped to their lowest in June and July, September offers a refreshing breeze that invigorates the coastal city. This trend of increasing winds is further underscored as October follows with 4.6 m/s, suggesting a steady return to the crisper, more dynamic weather patterns that characterize the later part of the year. With each passing month, Shimonoseki's winds play a subtle yet impactful role in shaping the local atmosphere, inviting residents and visitors alike to enjoy the beautiful coastal scenery.
Weather in Shimonoseki varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Shimonoseki, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. In September, temperatures range from a mild 18°C (65°F) to a warm 32°C (89°F), creating an average of 24°C (76°F). The month is also quite wet, with 226 mm (8.9 in) of precipitation over 12 days and a high humidity level of 84%. In contrast, January sees much cooler temperatures, with a minimum of -1°C (30°F) and a maximum of 17°C (64°F), averaging around 8°C (46°F). Precipitation drops significantly to 84 mm (3.3 in) over the same number of days, accompanied by a lower humidity level of 76%. For more detailed insights into winter conditions, check out Shimonoseki weather in January.
September and February present stark contrasts in weather. September boasts a warm climate with average temperatures around 24°C (76°F), reaching highs of 32°C (89°F), while February experiences a much cooler environment, with average temperatures of only 8°C (46°F) and a maximum of 18°C (65°F). Additionally, September is characterized by significant rainfall, with 226 mm (8.9 in) falling over 12 days, compared to February's more modest total of 93 mm (3.6 in) over 11 days. The humidity levels are also higher in September at 84%, compared to 72% in February, making the latter month feel much drier and crisper. For more detailed insights into the February weather, you can visit Shimonoseki weather in February.
September weather is characterized by warm temperatures, with a minimum of 18°C (65°F) and an average of 24°C (76°F), peaking at a maximum of 32°C (89°F). This month also experiences significant rainfall, totaling 226 mm (8.9 inches) over approximately 12 days, accompanied by high humidity levels averaging 84%. In contrast, March presents a distinctly cooler climate, with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 18°C (64°F) and an average of just 11°C (52°F). Although there is also precipitation in March, it is significantly lower at 165 mm (6.5 inches), also spread across 12 days, and the humidity is reduced to 69%. For more detailed information about the weather in March, you can visit Shimonoseki weather in March.
In comparing the weather of September and April, it is evident that September is significantly warmer, with average temperatures ranging from a minimum of 18°C (65°F) to a maximum of 32°C (89°F), while April experiences a cooler climate with temperatures peaking at 22°C (71°F). Additionally, September sees higher precipitation levels, accumulating 226 mm (8.9 in) over 12 days, compared to April's 129 mm (5.1 in) over just 10 days. Humidity also varies, with September's humidity at 84%, making it feel quite muggy, whereas April's 75% humidity levels offer a relatively fresher atmosphere. For those looking to explore the specifics of April weather, please refer to Shimonoseki weather in April.
In comparing the weather of September and May, September tends to be warmer, with temperatures ranging from a minimum of 18°C (65°F) to a maximum of 32°C (89°F), while May offers a cooler experience with temperatures ranging from 12°C (54°F) to 25°C (77°F). Both months share the same humidity level of 84%, contributing to a muggy atmosphere, but September sees significantly more precipitation, averaging 226 mm (8.9 in) over 12 days compared to May's 141 mm (5.5 in) over 10 days. This makes September not only warmer but also wetter than May. For a more detailed overview of May’s weather, you can check out Shimonoseki weather in May.
September weather tends to be warmer than June, with average temperatures reaching up to 24°C (76°F) compared to June's 21°C (71°F). September also sees higher maximum temperatures, peaking at 32°C (89°F) versus June's 27°C (81°F). However, September is characterized by increased precipitation, averaging 226 mm (8.9 in) over 12 days, compared to June's 194 mm (7.7 in) over 11 days. Both months experience high humidity levels, with September at 84% and June slightly higher at 88%. For a closer look at June's weather, check out Shimonoseki weather in June.
When comparing the weather in September and July, it's clear that both months share warm temperatures, but there are notable differences. In September, the minimum temperature averages 18°C (65°F) and the maximum reaches 32°C (89°F), with an average of 24°C (76°F). Conversely, July tends to be slightly warmer with a minimum of 20°C (69°F), an average of 25°C (78°F), and a maximum of 31°C (88°F). However, July experiences more precipitation, totaling 295 mm (11.6 in) over 16 days compared to September's 226 mm (8.9 in) over 12 days. Additionally, humidity levels are higher in July at 95%, compared to September's 84%. For more details, you can check Shimonoseki weather in July.
In comparing the weather patterns of September and August, September tends to be slightly cooler, with average temperatures ranging from a minimum of 18°C (65°F) to a maximum of 32°C (89°F), while August experiences higher averages, with minimums at 21°C (69°F) and an average of 27°C (81°F). Both months share a maximum temperature of 32°C (89°F), but September has slightly lower humidity at 84%, compared to August's 93%. Precipitation also decreases in September, with 226 mm (8.9 in) falling over 12 days, while August sees 251 mm (9.9 in) over 13 days. For a deeper dive into August's conditions, check out Shimonoseki weather in August.
September weather is characterized by warmer temperatures, with average highs reaching 32°C (89°F) and a notable humidity level of 84%. The month experiences significant rainfall, totaling 226 mm (8.9 in) over approximately 12 days. In contrast, October sees a marked drop in temperature, with average highs of 27°C (82°F) and a decrease in humidity to 79%. Precipitation also diminishes, totaling 121 mm (4.7 in) over 11 days. For more detailed insights, you can check Shimonoseki weather in October.
September and November present starkly contrasting weather conditions. In September, temperatures range from a minimum of 18°C (65°F) to a maximum of 32°C (89°F), with an average of 24°C (76°F), accompanied by high humidity at 84%. The month also sees significant rainfall, accumulating 226 mm (8.9 in) over 12 days. In contrast, November brings cooler temperatures, with a minimum of 8°C (46°F), an average of 15°C (59°F), and a maximum of 23°C (74°F). The precipitation drops considerably to 54 mm (2.1 in) over just 8 days, and humidity decreases to 76%. For a detailed look at the weather specifics in November, you can check Shimonoseki weather in November.
September and December present stark contrasts in weather. In September, temperatures range from a comfortable minimum of 18°C (65°F) to a maximum of 32°C (89°F), with an average of 24°C (76°F). This month is also characterized by high humidity at 84% and significant precipitation of 226 mm (8.9 in) over 12 days. In contrast, December ushers in much cooler temperatures, with a minimum of 1°C (34°F), an average of 10°C (50°F), and a maximum of 20°C (68°F). Precipitation decreases significantly to 89 mm (3.5 in), although it still occurs over the same number of days. Humidity also drops to 75%, making December feel much crisper and drier. For more details on December weather, you can visit Shimonoseki weather in December.
As September unfolds in Shimonoseki, the weather begins to shift from the sweltering heat of summer to a more temperate climate, with pleasant daytime temperatures and cooler evenings creating a refreshing atmosphere. This month is characterized by increased humidity and a notable rise in precipitation, contributing to the lush landscapes that define the region. With an average of 12 rainy days, September marks a transition, allowing for vibrant greenery while also signaling the gradual approach of autumn. For a deeper dive into the seasonal shifts and climatic nuances of this beautiful area, explore more at Shimonoseki Climate.