September Weather in Jiangnan, China

Last updated: August 21, 2025

In September, Jiangnan, China experiences a dynamic climate characterized by a maximum temperature soaring to 35°C (95°F), an average of 28°C (83°F), and a minimum of 21°C (70°F). This transitional month sees 233 mm (9.2 in) of precipitation spread across 23 days, contributing to a humid environment with an average humidity level of 75%. Visitors and locals alike can expect a mix of sunny spells and rainy days, making it essential to be prepared for various weather conditions while enjoying the region's vibrant autumn scenery.

September Temperature in Jiangnan

In September, Jiangnan, China, experiences a warm transition as summer gently fades into autumn. With minimum temperatures averaging around 21°C (70°F) and daily highs reaching 35°C (95°F), the month is characterized by notable warmth, although slightly cooler than the peak summer months of July and August. The average temperature of 28°C (83°F) reflects a lingering summer vibe, making it an ideal time for outdoor activities before the cooler October weather sets in. As humidity begins to decrease, September offers a pleasant balance, inviting both locals and travelers to embrace the beauty of the changing season amidst the lush landscapes of this picturesque region.

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

The chart illustrates September temperature patterns in Jiangnan, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Jiangnan, 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).
JanFebMarAprMayJunJulAugSepOctNovDec616270738084858483767062
Data source: Temperature data for Jiangnan 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 Jiangnan

In September, Jiangnan experiences a notable transition in its climatic rhythm, as the region receives 233 mm (9.2 in) of rainfall over 23 days. While this quantity is a decline from the previous month’s peak of 326 mm, the persistent rainfall signifies the lingering effects of the summer monsoon. This month reflects a continuation of the wetter trend established from June through August, with precipitation significantly surpassing earlier months like January and February. As the last vestiges of summer fade, September's showers not only nourish the lush landscapes but also set the stage for the drier autumn months ahead, hinting at a gradual shift toward the cooler season.

September Precipitation Trends in Jiangnan

The chart displays monthly precipitation patterns in Jiangnan, 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 Jiangnan, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec2156821272163152223262331432717
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Jiangnan

In September, Jiangnan, China experiences a noticeable dip in humidity, with levels averaging 75%. This marks a significant decrease from the peak summer months of July and August, where humidity soared to 88%. Interestingly, while September still maintains higher humidity compared to the drier months of October (65%) and November (64%), it indicates a gradual transition toward a more moderate climate. This seasonal shift reveals a typical pattern in Jiangnan's weather, where the intense summer mugginess begins to wane, paving the way for crisper autumn air. Overall, September serves as a bridge between the sweltering summer and the cool, refreshing fall.

September Average Humidity in Jiangnan

This chart illustrates the average monthly humidity levels in Jiangnan, 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 Jiangnan is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec64%68%73%71%79%77%88%88%75%65%64%69%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Jiangnan

As the summer fades, September in Jiangnan, China, still boasts a notably high UV Index of 11, categorized as extreme. This indicates that while the intensity of sunlight begins to slightly decrease from the peak levels seen in May through August, careful skin protection remains crucial, with a burn time of only 10 minutes if exposed without sunscreen. Notably, this month follows a trend of increasing UV exposure from earlier in the year—starting with a high index of 7 in January and reaching its peak in May at 14. As we transition to October, the UV Index drops to 10, signaling a welcome respite before the onset of winter. For more information on UV levels, visit Jiangnan UV Index.

Maximum UV Index Levels in Jiangnan for September

The chart shows the monthly maximum UV Index (UVI) for Jiangnan 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 Jiangnan typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec710121214131313111097
Data source: Jiangnan 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 Jiangnan

As the summer fades into autumn, September in Jiangnan, China, continues to bask in a generous 280 hours of sunshine, marking a delightful transition from the peak brightness of July. The sunshine steadily declines from July's high of 307 hours, but remains vibrant as the days grow shorter. This month enjoys slightly less sunlight than August's 276 hours, yet it holds its own, showcasing the lingering warm glow of summer while hinting at the crispness of fall. The consistent trend of abundant sunshine throughout the warmer months, especially from May to September, reflects Jiangnan's charm as a place where nature radiates beauty and warmth, captivating all who experience its gentle seasonal shift.

Monthly Sunshine Duration in Jiangnan: September Highlighted

The September sunshine duration represents the total number of hours Jiangnan 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.
JanFebMarAprMayJunJulAugSepOctNovDec202h233h236h236h287h277h307h276h280h271h260h263h
Data source: Jiangnan September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Jiangnan During September

As autumn unfolds in September, Jiangnan, China, experiences a notable increase in sunny weather with a 38% chance of sunshine. This marks a shift from the summer months, where sunny days are scarce, particularly in June and August, with chances plummeting to 10% and 14% respectively. Compared to the more dismal spring months, including March and April, September offers a welcome reprieve from the gloom, standing out within a year characterized by fluctuating sunshine. As the year progresses towards November, the chances of sunny days rise further to 62%, indicating a promising transition into early winter. So, while September may not guarantee a sun-drenched getaway, it certainly lays the groundwork for brighter days ahead.

Percentage of Sunny Days in September in Jiangnan

The chart illustrates the percentage of sunny days in Jiangnan 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 Jiangnan experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec56%51%28%30%29%10%29%14%38%33%62%48%
Data source: Jiangnan September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Jiangnan in September

As summer gracefully transitions into autumn, September in Jiangnan, China experiences a return to 12 hours of daylight, echoing the balanced brightness of spring months like March and April. This shift marks the end of the longer, sun-drenched days of the late summer months, where daylight peaked at 13 hours in May through July. As the year gently winds down, the diminishing daylight gradually heralds the approach of autumn, with the coming months promising a steady decline to the 11 hours of light seen in October and November. This rhythmic dance of daylight not only highlights the beauty of seasonal change but also invites reflection on the cyclical nature of time in this enchanting region.

Average Daylight Hours in Jiangnan for September

The chart illustrates the variation in daylight duration in Jiangnan throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 54m11h 23m12h 1m12h 40m13h 12m13h 28m13h 20m12h 52m12h 14m11h 36m11h 2m10h 45m
Data source: Jiangnan daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Jiangnan

As summer gives way to autumn in Jiangnan, the September wind whispers a gentle farewell, with an average speed of just 1.5 m/s (3 mph), the lightest breath of air recorded throughout the year. This significant drop from the summer months, where winds typically register around 1.9 to 2.2 m/s, illustrates a clear trend towards tranquility as nature prepares for the cooler days ahead. In contrast, the wind picks up again in October, reaching 3.5 m/s (8 mph), signaling a refreshing shift. This seasonal ebb and flow not only reflects the changing climate but also captures the serene beauty of Jiangnan, where each whisper of wind carries the promise of new beginnings.

Average September Wind Speed in Jiangnan

The chart displays monthly wind speed patterns in Jiangnan, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.82.22.72.42.62.42.21.91.5 m/s3.52.83.0
Data source: Jiangnan September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Jiangnan Compares to Other Months

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

September and January present contrasting weather patterns. In September, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), with an average of 28°C (83°F). This month is also marked by high humidity levels at 75% and significant precipitation, totaling 233 mm (9.2 in) over 23 days. In stark contrast, January features much cooler temperatures, with a minimum of 3°C (38°F) and a maximum of 28°C (83°F), averaging about 16°C (61°F). Precipitation is considerably lower in January, amounting to only 21 mm (0.8 in) across just 3 days, and humidity is reduced to 64%. For more detailed insights on January weather, you can visit Jiangnan weather in January.

September and February present markedly different weather conditions. In September, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), with an average of 28°C (83°F). This month is characterized by significant rainfall, receiving 233 mm (9.2 in) over 23 days, resulting in high humidity levels of around 75%. In contrast, February experiences much cooler temperatures, with a minimum of 4°C (40°F), an average of 17°C (62°F), and a maximum of 29°C (84°F). Additionally, February is drier, accumulating only 56 mm (2.2 in) of precipitation over 8 days and exhibiting a lower humidity of 68%. For more details about the weather in this region during February, you can visit Jiangnan weather in February.

In September, the weather is significantly warmer, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), and an average of 28°C (83°F). The month is also characterized by high humidity at 75% and substantial rainfall, with 233 mm (9.2 in) of precipitation spread over 23 days. In contrast, March brings much cooler temperatures, with a minimum of 9°C (48°F), an average of 21°C (70°F), and a maximum of 32°C (90°F). Rainfall is considerably lighter, totaling 82 mm (3.2 in) over just 15 days and a slightly lower humidity level at 73%. For a detailed overview of weather patterns during this month, check Jiangnan weather in March.

September and April present contrasting weather patterns. In September, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), with an average of 28°C (83°F). The month is marked by significant rainfall, receiving 233 mm (9.2 in) across about 23 days, alongside a humidity level of 75%. In contrast, April experiences milder temperatures, with a minimum of 11°C (53°F) and an average of 23°C (74°F), peaking at 33°C (92°F). Precipitation is also lower in April, totaling 127 mm (5.0 in) over approximately 14 rainy days, while humidity remains around 71%. For more information on how weather varies in this region, visit Jiangnan weather in April.

In September, the weather typically features warmer minimum temperatures, starting at 21°C (70°F) and reaching an average of 28°C (83°F) with highs peaking at 35°C (95°F). The month is characterized by significant rainfall, accumulating around 233 mm (9.2 in) over 23 days, and a humidity level of 75%.

In contrast, May brings slightly cooler minimum temperatures at 15°C (59°F) but averages a similar high of about 35°C (96°F) with an average of 27°C (80°F). Precipitation is slightly less, totaling 216 mm (8.5 in) over 20 days, and the humidity is marginally higher at 79%.

For more detailed insights into the weather conditions in May, check out Jiangnan weather in May.

In comparing the weather between September and June, we see that both months exhibit high temperatures, with June having slightly warmer average conditions. September's temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), averaging 28°C (83°F). In contrast, June starts at a minimum of 23°C (74°F) and reaches a maximum of 35°C (96°F) with an average of 29°C (84°F). Despite the similar high temperatures, June experiences a greater amount of precipitation at 315 mm (12.4 in) over 22 days, compared to September's 233 mm (9.2 in) over 23 days. The humidity level is slightly lower in June at 77% compared to September's 75%. For more detailed information about June weather, you can refer to this link: Jiangnan weather in June.

In comparing the weather patterns of September and July, September experiences slightly cooler temperatures with a minimum of 21°C (70°F) and a maximum of 35°C (95°F), as opposed to July’s higher minimum of 25°C (77°F) and maximum of 37°C (98°F). Overall, September averages 28°C (83°F), which is comparable to July's average of 29°C (85°F). Precipitation levels are quite similar, with September receiving 233 mm (9.2 in) over 23 days, while July sees 222 mm (8.7 in) also in 23 days. Notably, humidity is higher in July at 88%, compared to September's 75%. For a more detailed look at July's climate, check out Jiangnan weather in July.

In August, the weather tends to be slightly hotter and more humid, with minimum temperatures around 24°C (76°F) and maximums reaching up to 37°C (100°F). This month experiences heavy rainfall, averaging 326 mm (12.8 in) over 25 days, leading to an overall humidity level of 88%. In contrast, September sees a slight decrease in temperatures, with a minimum of 21°C (70°F) and a maximum of 35°C (95°F), while the average temperature is around 28°C (83°F). Although September still has considerable rainfall at 233 mm (9.2 in) over 23 days, the humidity drops to a more comfortable 75%. For a more detailed overview of August conditions, visit Jiangnan weather in August.

September typically experiences warmer temperatures, with a minimum of 21°C (70°F) and an average of 28°C (83°F), while October sees a drop, with temperatures ranging from a minimum of 15°C (60°F) to an average of 25°C (77°F). Although both months can reach a high of 35°C (95°F), October generally offers a more comfortable climate due to lower humidity levels of 65% compared to September's 75%. Additionally, October receives significantly less rainfall, accumulating around 143 mm (5.6 in) over just 12 days, in contrast to September's 233 mm (9.2 in) over 23 days. For more detailed information about October weather in the Jiangnan region, you can visit this link: Jiangnan weather in October.

September and November display a striking contrast in weather characteristics. In September, temperatures are notably higher, with minimums around 21°C (70°F) and maximums reaching up to 35°C (95°F), contributing to an average temperature of 28°C (83°F). This month also experiences substantial rainfall, totaling 233 mm (9.2 in) over 23 days, coupled with high humidity at 75%. In contrast, November sees a significant drop in temperature, with minimums dipping to 12°C (54°F) and maximums at 31°C (88°F), leading to a more comfortable average of 21°C (70°F). Precipitation in November is minimal, at just 27 mm (1.1 in) over only 5 days, and the humidity decreases to 64%. For more specific details on weather patterns during this month, you can check Jiangnan weather in November.

In September, the weather tends to be quite warm, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 35°C (95°F), while the average temperature sits at around 28°C (83°F). This month also sees considerable precipitation, with around 233 mm (9.2 in) falling over roughly 23 days, coupled with high humidity at 75%. In contrast, December experiences much cooler temperatures, with a minimum of 7°C (44°F) and a maximum of 29°C (84°F), averaging at 17°C (62°F). Rainfall drops significantly to just 17 mm (0.7 in) over 3 days, and humidity decreases slightly to 69%. For more detailed information, you can check Jiangnan weather in December.

Compare Jiangnan's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Jiangnan

As September unfolds in Jiangnan, the transition from the sweltering summer months becomes palpable. With an average temperature around 28°C (83°F), it offers a reprieve from the peak heat, while still occasionally flirting with maximums of 35°C (95°F). This month is marked by increased humidity levels and significant precipitation, with rain gracing roughly three-quarters of the days, making it notably wetter than preceding months. Such conditions not only enhance the region’s lush beauty but also set the stage for the vibrant autumn to come. For a deeper dive into Jiangnan's climate patterns, check out Jiangnan Climate.