Last updated: August 21, 2025
In Chiba, Japan, September brings a dynamic climate characterized by a maximum temperature soaring to 32°C (89°F) and a pleasant average of 24°C (75°F), while evenings cool down to a minimum of 16°C (60°F). This month is notably wet, with 232 mm (9.1 in) of precipitation recorded over 18 days, contributing to a high humidity level of 86%. Visitors can expect a mix of warm days and frequent rain, making it essential to stay prepared for all weather contingencies while enjoying the vibrant atmosphere of Chiba this time of year.
As summer transitions to autumn in Chiba, Japan, September marks a delightful shift in temperatures. With minimums lingering around 16°C (60°F) and reaching a comfortable average of 24°C (75°F), this month is a wonderful time to enjoy the outdoors before cooler weather sets in. The maximum temperatures can soar up to 32°C (89°F), making it one of the warmest months before winter approaches. Unlike the sweltering heights of July and August, September offers a pleasant warmth that invites both locals and visitors to relish in the lingering sunshine and explore the vibrant landscapes of Chiba. This gradual decline from the peak summer heat sets the stage for a cozy fall, perfect for festivals and outdoor activities.
In September, Chiba, Japan experiences a notable peak in precipitation, recording 232 mm (9.1 in) of rain over 18 days. This significant increase follows the monsoon-like conditions seen in the preceding months and sets the stage for October, which historically sees even more rainfall at 313 mm (12.3 in). The transition from summer to autumn is marked by this spike, as the lush greenery of the region is nourished by the abundant moisture. Notably, September's rainfall is not just heavy but also frequent, indicating the start of the wetter season, which stabilizes the climate before the cold months set in. This trend highlights the shift in weather patterns that characterize Chiba's dynamic climate.
In September, Chiba, Japan, experiences a notable humidity level of 86%, marking a slight decline from the peak months of summer. Typically, the region begins to transition from the sweltering July and August, with their oppressive humidity levels of 93% and 90%, respectively. As autumn approaches, this gradual decrease suggests a welcome shift, yet the air remains noticeably moist compared to the drier winter months that follow. Overall, September maintains a significant humidity level, reflecting Chiba's consistent tropical influences while hinting at the cooler, crisper conditions that are just around the corner.
In September, Chiba, Japan, sees a UV Index of 9, categorizing exposure as very high with a burn time of just 15 minutes. This marks a slight decrease from the peak of 11 during the intense summer months of June through August. While the UV intensity is still significant, it's a reminder of the shifting seasons, as the UV Index begins to ease into fall. It's essential for residents and visitors alike to stay vigilant against sun exposure during this time. For the latest updates on UV levels, check out Chiba UV Index.
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As summer bids farewell, September in Chiba, Japan, continues to bask in the sun with an impressive 234 hours of sunshine. This month marks a transition, reflecting a slight decline from the peak of 288 hours in August, yet it still enjoys a wealth of warm, sunny days reminiscent of summer. The trend of increasing sunshine hours from January to May showcases a steady climb, peaking in summer, while early autumn maintains a respectable level of brightness. Notably, September's sunny disposition sets the stage for the softer light of autumn, a delightful farewell to summer warmth before the cooler months arrive. This seasonal rhythm not only enriches the landscape but also enhances the outdoor experiences for locals and visitors alike.
September in Chiba, Japan, sees a notable decline in the likelihood of sunny weather, with only a 27% chance of sunshine. This marks a significant dip from the preceding months of July and August, where the probabilities hover around 35% to 38%. As summer transitions into autumn, the overall trend indicates a gradual decrease in sunny days, making September one of the cloudier months. This shift prepares residents and visitors alike for the upcoming embrace of the crisp autumn air, while a mix of overcast skies can be expected as the seasons change.
As September arrives in Chiba, Japan, daylight begins to gently wane, offering approximately 12 hours of sunlight—just a slight reduction after the peak summer months. This transition signals the gradual shift from the long, bright days of June through August, where daylight extended up to 14 hours. Following September, the daylight duration gently diminishes further, leading into the shorter days of autumn and the crispness of winter. Observing this pattern, it's clear that Chiba experiences vibrant daylight variations throughout the year, with a distinct ebb and flow that beautifully marks each season's passage.
As September arrives in Chiba, Japan, the average wind speed settles at 4.0 m/s (9 mph), reflecting a gentle shift from the bustling summer breezes. With a noticeable variation across the year, wind speeds tend to peak during the more temperate months of May and April, where they reach 5.0 m/s (11 mph) and 4.5 m/s (10 mph), respectively. The summer months show a slight decline, particularly in July, when the winds calm to 3.1 m/s (7 mph), likely mirroring the sultry heat. As autumn unfolds, wind speeds experience a subtle resurgence, hinting at a transitional phase in the weather. Comparatively, October welcomes a slight uptick back to 4.1 m/s (9 mph), suggesting a continued movement towards cooler, crisper air. Overall, September's breezes create a refreshing atmosphere, perfectly complementing the seasonal shift.
Weather in Chiba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Chiba, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present starkly contrasting weather conditions. In September, temperatures are warm, ranging from a minimum of 16°C (60°F) to a maximum of 32°C (89°F), with an average around 24°C (75°F). This month also experiences high humidity at 86% and significant rainfall, receiving 232 mm (9.1 in) over 18 days. In contrast, January brings much cooler temperatures, with minimums dropping to -2°C (28°F) and maximums peaking at 16°C (61°F), averaging around 6°C (43°F). Precipitation is considerably lower, with only 63 mm (2.5 in) over just 5 days, and humidity levels at 76%. For more details about January weather, visit Chiba weather in January.
September and February exhibit distinct differences in weather patterns. In September, temperatures range from a mild 16°C (60°F) at night to a warm 32°C (89°F) during the day, with an average of 24°C (75°F). The month is characterized by high humidity at 86% and significant rainfall, accumulating to 232 mm (9.1 in) over 18 days. In contrast, February presents a much cooler climate, with temperatures varying from a chilly 0°C (32°F) to a maximum of 16°C (62°F) and an average of just 7°C (44°F). Precipitation is considerably lower, totaling 50 mm (2.0 in) across only 7 days and featuring a lower humidity level of 74%. For those interested in more details about February weather in Chiba, please visit Chiba weather in February.
September and March exhibit markedly different weather patterns. In September, temperatures range from a mild minimum of 16°C (60°F) to a sweltering maximum of 32°C (89°F), with an average of 24°C (75°F). The month experiences significant rainfall, totaling 232 mm (9.1 in) across 18 days, and humidity levels are quite high at 86%. In contrast, March is much cooler, with temperatures starting at a brisk minimum of 1°C (34°F) and reaching a comfortable maximum of 20°C (68°F), averaging around 10°C (50°F). Precipitation in March is lower at 162 mm (6.4 in) over 13 days, and humidity is comparatively drier at 70%. For more detailed information, check out Chiba weather in March.
In September, the weather tends to be significantly warmer and more humid than in April. With average temperatures ranging from a minimum of 16°C (60°F) to a maximum of 32°C (89°F), September offers a much higher warmth compared to April's cooler averages of 4°C (40°F) to 24°C (76°F). Additionally, September experiences more precipitation, totaling 232 mm (9.1 inches) over 18 days, while April sees less rain at 137 mm (5.4 inches) across 11 days. The humidity in September is also higher at 86%, compared to April's 74%. For more details about April weather specifically, check out Chiba weather in April.
In comparing the weather between September and May, September tends to be warmer and more humid. The average temperature in September is 24°C (75°F), with highs reaching up to 32°C (89°F), whereas May averages a cooler 19°C (66°F), with a maximum of 27°C (81°F). Additionally, September experiences significantly higher rainfall, with 232 mm (9.1 in) falling over 18 days, compared to May's 147 mm (5.8 in) over just 12 days. Humidity levels are also higher in September at 86%, compared to 81% in May. For more specific details on May's weather, you can check Chiba weather in May.
September and June weather show both similarities and differences, presenting a transition in climate as summer comes to an end. In September, the average temperature rises slightly to 24°C (75°F) with a maximum of 32°C (89°F) and a minimum of 16°C (60°F), while June features an average of 22°C (71°F), with similar low temperatures but a slightly lower high of 31°C (88°F). Precipitation is notably higher in September, totaling 232 mm (9.1 in) over 18 days compared to June's 190 mm (7.5 in) across 14 days. Humidity levels remain high in both months, with September at 86% and June slightly higher at 88%. For more detailed insights, you can check Chiba weather in June.
In comparing the weather of September and July, September sees slightly cooler temperatures, with a minimum of 16°C (60°F) and an average of 24°C (75°F), as opposed to July's warmer minimum of 19°C (66°F) and average of 25°C (78°F). July experiences a higher maximum temperature of 36°C (97°F), making it the hotter month overall. Precipitation levels are relatively similar, with September receiving 232 mm (9.1 in) over 18 days, while July has 226 mm (8.9 in) over 16 days. Additionally, July's humidity is slightly higher at 93%, compared to September's 86%. For more details, visit Chiba weather in July.
In comparing the weather conditions of September and August, we observe that September experiences slightly cooler temperatures, with a minimum of 16°C (60°F) and an average of 24°C (75°F), compared to August's minimum of 20°C (69°F) and an average of 27°C (81°F). However, September is notably wetter, with precipitation reaching 232 mm (9.1 in) over 18 days, while August sees only 118 mm (4.7 in) over 13 days. Humidity remains high in both months, but it's marginally lower in September at 86% compared to August's 90%. Overall, September marks a transition towards cooler and wetter weather after the hotter and drier conditions of August. For more details on August weather, visit Chiba weather in August.
September and October present notable shifts in weather patterns. In September, temperatures typically range from a minimum of 16°C (60°F) to a maximum of 32°C (89°F), with an average of 24°C (75°F). The month experiences significant precipitation, totaling 232 mm (9.1 in) over 18 days, alongside high humidity levels at 86%. In contrast, October sees cooler temperatures, with a minimum of 11°C (53°F) and an average of 19°C (66°F), peaking at 28°C (83°F). Precipitation increases further to 313 mm (12.3 in) over 17 days, while humidity slightly decreases to 83%. For more details on the specific weather conditions in October, you can visit Chiba weather in October.
September and November exhibit stark contrasts in weather. In September, temperatures range from a minimum of 16°C (60°F) to a maximum of 32°C (89°F), with an average of 24°C (75°F). This month is significantly wetter, receiving 232 mm (9.1 in) of precipitation over 18 days and maintaining a high humidity level of 86%. In contrast, November brings cooler temperatures, with a minimum of 5°C (41°F), an average of 14°C (58°F), and a maximum of 21°C (71°F). Precipitation decreases to 119 mm (4.7 in) over just 12 days, accompanied by a lower humidity of 80%. This transition marks a shift from the warm, humid days of early autumn to the crisp, cooler feel of late fall. For more details on the weather in November, visit Chiba weather in November.
September and December showcase stark contrasts in weather, reflecting the transition from late summer to early winter. In September, temperatures range from a minimum of 16°C (60°F) to a maximum of 32°C (89°F), with an average of 24°C (75°F). The month also experiences significant rainfall, with 232 mm (9.1 in) of precipitation over 18 days and high humidity at 86%. In contrast, December brings cooler conditions, with temperatures dropping to a minimum of 0°C (33°F) and an average of 9°C (48°F), peaking at 20°C (68°F). Additionally, December sees less rainfall at 80 mm (3.2 in) across just 8 days and lower humidity levels at 78%. For more details on December weather, check out Chiba weather in December.
As summer transitions to autumn, September in Chiba showcases a shift in weather patterns that distinguishes it from the preceding months. Temperatures remain warm, but with a notable increase in humidity and rainfall, making it one of the wetter months of the year. With frequent precipitation over 18 days, this period tends to feel more humid and lush compared to the drier summer months, resulting in a vibrant landscape. These climatic characteristics create a unique atmosphere that can be both refreshing and challenging. For an in-depth look at how the overall climate shapes your experience in Chiba, be sure to check out Chiba Climate.