Last updated: August 21, 2025
September in Imabari-shi, Japan, brings a blend of warm temperatures and notable humidity. The maximum temperature can reach up to 31°C (88°F), while the average hovers around 24°C (75°F), with nightly lows dipping to 17°C (63°F). This month is characterized by a significant precipitation total of 222 mm (8.7 in), occurring over approximately 15 days, contributing to the region's lush landscapes. With humidity levels soaring to 85%, visitors can expect a muggy atmosphere, making it essential to prepare for both warmth and the likelihood of rain.
In September, Imabari-shi experiences a delightful transition into autumn, with temperatures reflecting a satisfying warmth before the cooler months set in. The minimum temperature hovers around 17°C (63°F), while the average reaches a pleasant 24°C (75°F), peaking at a comfortable 31°C (88°F). This month marks a subtle drop from the sweltering summer highs of August but still offers plenty of warm days ideal for enjoying the vibrant scenery. As the heat of summer gives way to the crispness of autumn, September is a beautiful reminder of nature's cyclical charm in this picturesque Japanese city.
In September, Imabari-shi experiences a noteworthy increase in precipitation, receiving 222 mm (8.7 in) over 15 days of rain. This marks a significant uptick from the previous month, reflecting the peak of the wet season as summer transitions to autumn. Following the heavy rains of July—which recorded a staggering 360 mm (14.2 in)—September's rain continues to nurture the lush landscapes of the region. Although it experiences slightly less rainfall than October's 232 mm (9.2 in), the consistency and frequency of rain during September help sustain the lush greenery Imabari is known for, setting the stage for the changing seasons ahead.
In Imabari-shi, Japan, September marks a slight decrease in humidity, settling at 85%, yet it remains noticeably high. Following the summer months, which boast the peak humidity levels of 91% in July and 88% in August, September's readings indicate a gradual transition into autumn. The trend throughout the year shows a distinct pattern: humidity tends to climb from the cooler months of January to May before reaching their zenith in the summer. As the year progresses towards October, humidity levels begin to decline, suggesting a shift towards drier air. Overall, September encapsulates this seasonal change, offering a humid but slightly more comfortable atmosphere as the sweltering heat of summer begins to wane.
As summer wanes and September arrives in Imabari-shi, Japan, residents and visitors can expect the UV Index to remain notably high, registering at 10. This very high level of UV radiation means that a mere 15 minutes of unprotected sun exposure could result in skin burns. Maintaining awareness of sun safety is crucial as we transition from the scorching months of July and August, when the index peaked at an extreme 12. October will bring some relief, with a drop to 7; however, September’s elevated index highlights the continuous need for protection from harmful rays, especially as outdoor activities remain popular in the mild autumn climate. For more detailed information on UV levels, check the Imabari-shi UV Index.
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In September, Imabari-shi basks in the gentle warmth of 265 sunshine hours, marking a transition as summer begins to ebb. This month typically sees a slight decrease from the sun-drenched heights of August, which boasts an impressive 313 hours. It's noteworthy that September still enjoys robust sunlight, sustaining the vibrant atmosphere created during the peak of summer. As the seasons change, the trend reflects an overall gradual decline in daylight hours, yet September manages to remain a bright chapter in the year, standing out as a soft farewell to summer's brilliance before the cooler months of October and November take center stage.
In Imabari-shi, Japan, September marks the transition towards more favorable weather, with a 30% chance of sunny days. This slight increase in sunshine likelihood is notable when compared to the summer months, where figures dip as low as 23% in June and 25% in July. Although the chance remains lower than the autumn months, notably 55% in October, September bridges the gap between vibrant summer and the crisp fall, offering a hint of optimism for sun seekers. As the year progresses, you'll find that overall sun chances gradually enhance, making September a subtle turning point in the weather patterns of Imabari-shi.
In September, Imabari-shi experiences a gentle transition as daylight duration starts to taper off, offering approximately 12 hours of light each day. This follows the peak summer months of July and August, which bask in 14 and 13 hours of daylight, respectively. As the year progresses, daylight gradually wanes, moving from 14 hours in June down to 10 hours by November. The shift from the vibrant, sun-soaked days of summer to the crisper, shorter days of autumn signals a change in the natural rhythm of the region, inviting the beauty of fall to grace the landscape with its captivating hues.
As September unfolds in Imabari-shi, Japan, the average wind speed reaches a gentle 2.8 m/s (6 mph), offering a noticeable shift from the summer's languid breezes. Following the peak winds of January and December, which hover near 3.9 m/s (9 mph) and 4.2 m/s (9 mph) respectively, September's winds hint at the approaching autumn, transitioning smoothly from the milder gusts seen in the summer months. This time of year, the air becomes crisper, as the winds begin to pick up once again, signaling the gradual return to more invigorating conditions that will characterize the fall. Overall, September serves as a delicate bridge, inviting residents and visitors alike to enjoy the serene shifts in Imabari’s atmospheric dance.
Weather in Imabari-shi varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Imabari-shi, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present a striking contrast in weather conditions. In September, temperatures range from a mild 17°C (63°F) at night to a warm peak of 31°C (88°F) during the day, accompanied by significant humidity at 85% and frequent rainfall, averaging 222 mm over 15 days. In contrast, January brings a chill, with temperatures dipping to a minimum of -3°C (27°F) and reaching an average of only 6°C (42°F) during the day, coupled with much lower precipitation of 58 mm over 9 days and a humidity level of 74%. For more details on January's weather, visit Imabari-shi weather in January.
September and February present stark contrasts in weather. In September, temperatures range from a mild 17°C (63°F) at night to a warm 31°C (88°F) during the day, and the month is notable for its high humidity at 85%. Rainfall is significant, with 222 mm (8.7 in) spread over 15 days, making it one of the wetter months. In contrast, February experiences much colder temperatures, with a minimum of -2°C (29°F) and a maximum of 17°C (62°F), featuring a more temperate average of 6°C (43°F). Precipitation is also lower at 82 mm (3.2 in) over 10 days, and the humidity is reduced to 70%. For more details about February weather in Imabari, you can check Imabari-shi weather in February.
When comparing the weather in September and March, a notable difference emerges in temperature and humidity levels. September boasts a warm average temperature of 24°C (75°F), ranging from a comfortable 17°C (63°F) at its lowest to a hot 31°C (88°F) at its peak. In contrast, March is considerably cooler, with an average temperature of just 10°C (49°F) and minimum lows dropping to 1°C (34°F). Additionally, September experiences higher humidity at 85% compared to March's 70%, contributing to a muggy atmosphere. Precipitation is also more frequent in September, with 222 mm (8.7 in) falling over 15 days, while March sees 126 mm (5.0 in) over 12 days. For a closer look at the specifics of March weather, you can visit Imabari-shi weather in March.
September and April exhibit contrasting weather characteristics. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 31°C (88°F), with an average of 24°C (75°F). This month also sees significant rainfall, totaling 222 mm (8.7 in) over approximately 15 days, coupled with high humidity at 85%. In comparison, April experiences much cooler conditions, with temperatures ranging from 4°C (39°F) to 22°C (72°F) and an average of 13°C (56°F). Rainfall is more modest in April, amounting to 137 mm (5.4 in) over about 9 days, along with a lower humidity of 76%. For more details on April weather, check out Imabari-shi weather in April.
September and May present contrasting weather patterns. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 31°C (88°F), with an average of 24°C (75°F). This month is quite humid, reaching 85%, and experiences significant precipitation, totaling 222 mm (8.7 in) across approximately 15 days. In contrast, May is cooler, with temperatures varying from a minimum of 9°C (48°F) to a maximum of 26°C (78°F), averaging around 18°C (64°F). Precipitation in May is lighter, with 149 mm (5.8 in) over 11 days and a slightly lower humidity of 82%. This highlights May as a milder and drier month compared to the warm and wet conditions of September. For more details on May weather, visit Imabari-shi weather in May.
In September, the weather tends to be warmer compared to June, with average temperatures reaching 24°C (75°F) as opposed to June's 21°C (70°F). Peak temperatures in September can soar to 31°C (88°F), making it noticeably hotter than the maximum of 28°C (82°F) experienced in June. Additionally, September sees a higher total precipitation of 222 mm (8.7 in) compared to June's 195 mm (7.7 in), and both months have similar rainfall frequency, averaging 15 days of rain. Humidity levels are also quite similar, with September at 85% and June slightly higher at 86%. For more specific insights into June weather, you can check Imabari-shi weather in June.
September and July share similar maximum temperatures, both reaching up to 31°C (88°F), but September tends to be slightly cooler overall with an average temperature of 24°C (75°F) compared to July's 25°C (78°F). July experiences higher humidity at 91%, compared to September's 85%, making it feel muggier overall. Additionally, July sees more rainfall, with a total of 360 mm (14.2 in) over 19 days compared to September's 222 mm (8.7 in) over 15 days. For more specifics on July weather, you can visit Imabari-shi weather in July.
In comparing the weather between August and September, we observe that September experiences slightly cooler temperatures, with a minimum of 17°C (63°F) and an average of 24°C (75°F), compared to August's minimum of 20°C (68°F) and an average of 27°C (81°F). Furthermore, September sees a higher amount of precipitation at 222 mm (8.7 in) over 15 days, whereas August has 181 mm (7.1 in) over 13 days. Humidity levels are marginally lower in September at 85%, compared to August's 88%. For more detailed information, you can check Imabari-shi weather in August.
September and October present noticeable shifts in weather patterns. In September, temperatures are warmer, with a minimum of 17°C (63°F) and an average high of 31°C (88°F), while humidity hovers around a high 85%. The month experiences significant rainfall, totaling 222 mm (8.7 in) over 15 days. In contrast, October sees a drop in temperatures, with a minimum of 10°C (51°F) and an average maximum of 28°C (83°F). While precipitation slightly increases to 232 mm (9.2 in), it occurs over fewer days, totaling 11. Humidity also decreases slightly to 82%. For a detailed look at the weather specific to this month, you can check out Imabari-shi weather in October.
In September, the weather is typically warm with temperatures ranging from a minimum of 17°C (63°F) to a maximum of 31°C (88°F), averaging around 24°C (75°F). The month experiences significant rainfall, with 222 mm (8.7 in) recorded over 15 days, and humidity levels are relatively high at 85%. In contrast, November features much cooler temperatures, with a minimum of 4°C (40°F) and an average of 13°C (56°F), peaking at 23°C (73°F). Precipitation is also lower, totaling 62 mm (2.4 in) over just 8 days, and the humidity decreases slightly to 79%. To see more about how November weather feels in this area, check out Imabari-shi weather in November.
September and December present starkly contrasting weather patterns. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 31°C (88°F), with an average temperature of 24°C (75°F). The month is characterized by high humidity at 85% and significant rainfall, totaling 222 mm (8.7 in) over approximately 15 days. In contrast, December experiences much cooler temperatures, with a minimum of 0°C (33°F), an average of 8°C (47°F), and a maximum of 20°C (69°F). Precipitation decreases to 73 mm (2.9 in) spread over about 10 days, while humidity falls to 77%. For more details on December weather, visit Imabari-shi weather in December.
As September rolls in, Imabari-shi experiences a notable shift in weather dynamics compared to the summer months. The warmth persists with a comfortable average temperature, yet the increased humidity and frequent precipitation create a more dynamic climate, signaling the transition into autumn. With around half the month marked by rain, the lush landscapes of Imabari thrive, offering a refreshing environment. This blend of warmth and moisture sets September apart, making it a unique month for both residents and visitors alike. For a deeper dive into the weather patterns throughout the year, explore the Imabari-shi Climate.