September Weather in Oita, Japan

Last updated: August 21, 2025

In Oita, Japan, September greets visitors with warm temperatures ranging from a maximum of 32°C (90°F) to a pleasant average of 24°C (76°F), cooling down to a minimum of 15°C (59°F) at night. As the month unfolds, it presents a lush ambiance, characterized by high humidity levels at 84%. However, this tropical feel comes with significant rainfall, totaling 218 mm (8.6 inches) across approximately 16 days, creating a vibrant yet moist environment that perfectly encapsulates the essence of early autumn in this charming region.

September Temperature in Oita

In September, Oita, Japan experiences a pleasant transition from the sweltering summer months to the mild beginnings of autumn. With minimum temperatures around 15°C (59°F) and an average of 24°C (76°F), the weather invites outdoor exploration and vibrant fall activities. The maximum temperature can reach 32°C (90°F), reminding us that summer’s warmth lingers just a bit longer. This month marks a sweet spot in the year, where the days still feel warm but the evenings begin to cool, creating a perfect blend for enjoying Oita's natural beauty. As summer's humidity recedes, visitors can look forward to crisp, refreshing evenings, making September an ideal time to experience the charm of this scenic region.

September Weather in Oita: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Oita, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Oita, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec434451586773808275665646
Data source: Temperature data for Oita generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Oita

In September, Oita, Japan, experiences a significant amount of rainfall, with precipitation reaching 218 mm (8.6 in) over 16 days. This marks a slight decrease from the deluge of the preceding months, yet it remains substantial, indicative of the region's late-summer monsoon influences. Following the record rainfall in July (325 mm) and a still considerable August (228 mm), September’s precipitation continues to underscore a trend of increased moisture characteristic of the season. As the temperatures begin to cool with the onset of autumn, the enduring rainfall serves as a reminder of the transition from the humid summer months, providing vital support to Oita’s lush landscapes.

September Precipitation Trends in Oita

The chart displays monthly precipitation patterns in Oita, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Oita, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec52671161071431913252282181834753
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Oita

September in Oita, Japan, brings a welcome respite from the sweltering summer months, with humidity levels easing to 84%. After the peak of 92% in July and 91% in August, the humidity begins to decline, reflecting the transition into autumn. This month still retains a significant amount of moisture in the air, characteristic of the region's humid subtropical climate. As temperatures cool and the air becomes slightly drier, September serves as a gentle reminder of the seasonal shift, inviting residents and visitors alike to enjoy the beautiful changing landscapes without the oppressive humidity that marked the height of summer.

September Average Humidity in Oita

This chart illustrates the average monthly humidity levels in Oita, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Oita is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec75%71%71%78%84%86%92%91%84%83%81%79%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Oita

In September, Oita, Japan, retains an extreme UV Index of 11, mirroring the intensity seen in the sweltering summer months of July and August. This consistent high level indicates that outdoor enthusiasts should remain vigilant, as the burn time is a mere 10 minutes. While the UV Index begins to dip in October, transitioning to a high category of 7, September still reflects a lingering summer sun, emphasizing the importance of sun protection. As you navigate the bright days of early autumn, make sure to equip yourself with sunscreen and protective clothing to enjoy the outdoors safely. For more detailed insights, visit Oita UV Index.

Maximum UV Index Levels in Oita for September

The chart shows the monthly maximum UV Index (UVI) for Oita in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Oita typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec469111211121211764
Data source: Oita September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Oita

September in Oita, Japan, continues the delightful trend of abundant sunshine that peaks during the summer months. With 254 hours of sunshine, September remains vibrant and inviting, though it sees a slight decline from August's spectacular 297 hours. This transition marks the beginning of autumn, as warm days linger and the landscape begins to shift in color. Throughout the year, the sunlight gradually climbs from 181 hours in January to a summer high, demonstrating a clear seasonal rhythm that captivates both locals and visitors. As daylight diminishes in October to 249 hours, September serves as a beautiful bridge to the cooler months, offering a perfect blend of warmth and early autumn charm.

Monthly Sunshine Duration in Oita: September Highlighted

The September sunshine duration represents the total number of hours Oita experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec181h231h264h280h286h258h266h297h254h249h235h221h
Data source: Oita September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Oita During September

In Oita, Japan, September offers a 31% chance of sunny weather, signaling a gradual improvement as the year progresses. This figure stands out against the backdrop of the summer months, where July and August experience the lowest likelihood of sunshine, dipping to just 17% and 24%, respectively. As autumn approaches, the prospect of clearer skies begins to rise again, aligning with a noticeable upswing in October's sunny forecast at 55%. Overall, while September may not guarantee sun-soaked days, it hints at a transition towards brighter weather, making it a promising time to enjoy Oita's exquisite scenery before the chill of winter sets in.

Percentage of Sunny Days in September in Oita

The chart illustrates the percentage of sunny days in Oita throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Oita experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec46%50%39%43%31%20%17%24%31%55%53%58%
Data source: Oita September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Oita in September

As September unfolds in Oita, Japan, the days begin to gradually shorten, with daylight lasting 12 hours. Following the vibrant summer months of July and August, which boasted 14 and 13 hours of sunlight respectively, September marks a transitional phase where the lingering warmth of summer starts to give way to the cooler autumn air. This decrease in daylight is mirrored in the steady decline observed after the peak summer months, leading into October’s 11 hours and November’s 10 hours. Notably, this pattern reflects a rhythmic ebb and flow, showcasing nature’s cycle as daylight transitions from the long, sun-drenched days of summer to the cozy, shorter days of fall.

Average Daylight Hours in Oita for September

The chart illustrates the variation in daylight duration in Oita throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 12m10h 58m11h 58m13h13h 52m14h 18m14h 5m13h 19m12h 20m11h 19m10h 26m9h 58m
Data source: Oita daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Oita

In September, Oita, Japan, experiences a gentle breeze with an average wind speed of 1.9 m/s (4 mph), continuing the trend of softer winds that characterizes the late summer months. Following a gradual decline throughout the summer, where July and August saw the coolest breezes at just 1.8 m/s, September marks a slight uptick, hinting at a subtle transition as autumn approaches. This month often serves as a bridge, where warmer days meld with the crispness of early fall, offering residents and visitors alike a perfect opportunity to enjoy the serene atmosphere as nature begins to shift. As the winds pick up slightly in the coming months, Oita transitions gracefully from the languid summer days to the invigorating briskness of autumn.

Average September Wind Speed in Oita

The chart displays monthly wind speed patterns in Oita, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.83.02.32.52.11.91.91.81.9 m/s2.02.43.0
Data source: Oita September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Oita Compares to Other Months

Weather in Oita varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Oita, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present contrasting climates, reflecting a significant seasonal shift. In September, temperatures range from a mild 15°C (59°F) at night to a warm 32°C (90°F) during the day, with an average of 24°C (76°F). The month is also characterized by high humidity at 84% and considerable rainfall, totaling 218 mm (8.6 in) over 16 days. In stark contrast, January experiences much cooler conditions, with temperatures dipping as low as -3°C (26°F) at night and only reaching a maximum of 17°C (63°F) during the day. Precipitation in January is minimal, at just 52 mm (2.0 in) over 5 days, and humidity decreases to 75%. For more detailed information on January weather, visit Oita weather in January.

September and February present distinct contrasts in weather. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 32°C (90°F), creating a warm and humid atmosphere with an average of 24°C (76°F). This month experiences significant rainfall, with about 218 mm (8.6 in) falling over 16 days and humidity levels at 84%. In contrast, February brings a much cooler climate, with temperatures dipping to a minimum of -3°C (26°F) and peaking at 20°C (68°F), averaging around 7°C (44°F). The precipitation is notably lower at 67 mm (2.6 in) over just 8 days, and humidity is reduced to 71%. For more details on February weather, visit Oita weather in February.

September and March present a stark contrast in weather conditions. September typically experiences warmer temperatures, with minimums around 15°C (59°F) and maximums reaching up to 32°C (90°F). In contrast, March is much cooler, with nightly lows dropping to 1°C (35°F) and daytime highs averaging 24°C (76°F). Additionally, September is characterized by higher humidity levels at 84% and significant precipitation, averaging 218 mm (8.6 in) over 16 days. On the other hand, March sees lower humidity at 71% and less rainfall, averaging 116 mm (4.6 in) over just 11 days. For more detailed information, you can check out Oita weather in March.

September and April present contrasting weather patterns. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 32°C (90°F), with an average of 24°C (76°F). The month is characterized by higher precipitation, totaling 218 mm (8.6 in) across 16 rainy days and a noticeably high humidity level of 84%. In stark contrast, April features cooler weather, with temperatures dipping to a minimum of 3°C (38°F) and peaking at 25°C (78°F), averaging 14°C (58°F). April also sees less rainfall, with just 107 mm (4.2 in) over 8 days and a humidity of 78%. For more specifics on April's climate, you can check out Oita weather in April.

September and May offer distinct weather experiences, with September generally being warmer and wetter. In September, temperatures can range from a minimum of 15°C (59°F) to a maximum of 32°C (90°F), with an average of 24°C (76°F). This month also sees considerable rainfall, averaging 218 mm (8.6 in) over 16 days, contributing to high humidity levels of 84%. In contrast, May tends to be milder, with temperatures ranging from 8°C (46°F) to 30°C (87°F) and an average of 19°C (67°F). May experiences less precipitation, totaling 143 mm (5.6 in) over just 11 days, yet maintains the same humidity level of 84%. For more details on May weather, you can check Oita weather in May.

In comparing September and June weather, both months exhibit similar temperature ranges, with September experiencing a minimum of 15°C (59°F) and an average of 24°C (76°F), while June has a slightly cooler minimum of 14°C (57°F) and an average of 23°C (73°F). Both months reach a maximum temperature of 32°C (90°F for September and 89°F for June), but September sees more precipitation, totaling 218 mm (8.6 in) over 16 days compared to June's 191 mm (7.5 in) over 15 days. Humidity levels are also quite comparable, with September at 84% and June slightly higher at 86%. For more specific details about June weather in Oita, you can visit Oita weather in June.

In comparing the weather between September and July, we notice some distinct differences. September typically enjoys a milder temperature range, with minimums around 15°C (59°F) and averages of 24°C (76°F), while July tends to be warmer, with minimums of 19°C (67°F) and average temperatures of 26°C (80°F). However, July experiences higher maximum temperatures, peaking at 34°C (94°F) compared to September's 32°C (90°F). Precipitation also differs, with July receiving 325 mm (12.8 in) over 21 days, notably more than September's 218 mm (8.6 in) across 16 days. Humidity levels are slightly higher in July at 92%, compared to September's 84%. For more detailed information, you can check out Oita weather in July.

In comparing the weather between September and August, September experiences slightly cooler temperatures, with a minimum of 15°C (59°F) and a maximum of 32°C (90°F), averaging around 24°C (76°F). In contrast, August is warmer, with a minimum of 20°C (69°F) and a maximum reaching 36°C (97°F), averaging 28°C (82°F). While both months see a considerable amount of precipitation, September receives 218 mm (8.6 in) across 16 days, slightly less than August's 228 mm (9.0 in) over 15 days. Humidity levels also decrease moderately from August's 91% to September's 84%. For a detailed look at August weather, visit Oita weather in August.

As September transitions into October, we observe a notable shift in weather patterns. September typically boasts warmer temperatures, with an average of 24°C (76°F) and highs reaching up to 32°C (90°F), while October cools down significantly, featuring an average temperature of 19°C (67°F) and a maximum of 30°C (86°F). Precipitation levels are also slightly lower in October, with 183 mm (7.2 in) of rain over approximately 10 days, compared to September's 218 mm (8.6 in) spread across 16 days. Despite the decrease in temperature and rain, October maintains a relatively high humidity level at 83%, just slightly lower than September's 84%. For more detailed insights, you can check Oita weather in October.

September and November experience quite different weather conditions. In September, temperatures range from a comfortable minimum of 15°C (59°F) to a warm maximum of 32°C (90°F), with an average of 24°C (76°F). This month also experiences considerable rainfall, totaling 218 mm (8.6 in) over 16 days, and humidity levels are high at 84%. In contrast, November's temperatures drop significantly, with a minimum of 4°C (39°F), an average of 13°C (56°F), and a maximum of 25°C (76°F). The precipitation is much lighter, at just 47 mm (1.8 in) over 6 days, and humidity decreases slightly to 81%. For more details on November conditions, you can visit Oita weather in November.

September and December present stark contrasts in weather. In September, temperatures are quite warm, with a minimum of 15°C (59°F) and a maximum reaching up to 32°C (90°F), making it feel much more summery. However, this month is characterized by higher precipitation, averaging 218 mm (8.6 in) over 16 days, along with a high humidity level of 84%. In comparison, December sees a significant drop in temperature, with averages ranging from a chilly minimum of -1°C (31°F) to a comfortable maximum of 22°C (72°F). The precipitation decreases to 53 mm (2.1 in) over just 6 days, and humidity drops slightly to 79%. For more detailed information about the weather during this month, you can check Oita weather in December.

Compare Oita's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Oita

As summer transitions to autumn in Oita, September brings a unique blend of warmth and moisture that sets it apart from other months. With average temperatures hovering around 24°C (76°F) and maximums reaching up to 32°C (90°F), residents and visitors alike experience the lingering heat before cooler days arrive. However, September's high humidity—averaging 84%—combined with significant rainfall, averaging 218 mm (8.6 in) over 16 rainy days, creates a distinct, sultry atmosphere. This dynamic weather pattern not only influences daily activities but also enhances the region's lush landscapes, showcasing Oita's natural beauty in a vibrant transitional phase. For more insights on weather patterns throughout the year, check out Oita Climate.