September Weather in Chengdu, China

Last updated: August 21, 2025

Experience the vibrant September weather in Chengdu, China, where temperatures range from a warm 14°C (57°F) at night to a sizzling maximum of 35°C (95°F) during the day. The average temperature sits comfortably at 22°C (73°F), making it an ideal time for outdoor adventures. However, be prepared for some moisture, as the city receives about 118 mm (4.6 in) of rainfall over 14 days, contributing to a high humidity level of 92%. Whether basking in the sun or enjoying the refreshing rain, September in Chengdu offers a unique climate experience.

September Temperature in Chengdu

In September, Chengdu experiences a pleasant transition as summer gives way to autumn. With temperatures ranging from a minimum of 14°C (57°F) to a comfortable average of 22°C (73°F), the city enjoys warm days well into the season. The peak temperature reaches a maximum of 35°C (95°F), providing ample opportunities for outdoor activities and exploration. This month marks a gradual cooling trend from the sweltering heat of August, which recorded highs topping 40°C (104°F), making September an ideal time for both locals and tourists to enjoy Chengdu's vibrant culture and picturesque scenery without the intense summer heat.

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

The chart illustrates September temperature patterns in Chengdu, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Chengdu, 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).
JanFebMarAprMayJunJulAugSepOctNovDec444858667278808072635545
Data source: Temperature data for Chengdu generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Chengdu

September in Chengdu marks a noticeable transition in the city's weather patterns, as the summer rainfall begins to taper off. With 118 mm (4.6 in) of precipitation over 14 days, it's a significant drop from the previous months but still maintains a damp atmosphere. This period sees a shift from the torrential downpours characteristic of July and August, allowing for a gentler mix of rain and sunshine. The decrease in total precipitation compared to the peak summer months hints at the onset of autumn, where the region begins to experience drier spells ahead. Still, September's affable weather offers a refreshing change, as the city readies itself for the cooler months of October and November.

September Precipitation Trends in Chengdu

The chart displays monthly precipitation patterns in Chengdu, 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 Chengdu, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec51023587489313409118571511
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Chengdu

In Chengdu, China, September marks a continuation of the city's typically high humidity levels, which hover around a notable 92%. This month, along with its preceding counterpart, August, showcases the peak of humidity for the year, reflecting an atmosphere thick with moisture. Interestingly, after the summer months, where humidity remains consistently in the upper 80s and low 90s, September reflects a slight plateau that carries into the fall. Following this humid stretch, the levels gradually stabilize through the autumn months, maintaining a persistent 92% into October and November. This trend suggests that while Chengdu experiences a vibrant and damp summer, the transition into fall introduces a sustained humidity that creates a unique, lush environment year-round.

September Average Humidity in Chengdu

This chart illustrates the average monthly humidity levels in Chengdu, 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 Chengdu is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec90%92%90%86%87%88%89%92%92%92%92%90%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Chengdu

As September unfolds in Chengdu, China, the UV Index peaks at 11, categorizing it as extreme with a burn time of just 10 minutes. This trend of high UV exposure continues from the scorching months of summer, where June and July also recorded an index of 11. Following a gradual rise from a moderate index of 5 in January to an alarming peak in May, it’s clear that the risk of sunburn and UV-related health issues remains significant, compelling residents and visitors alike to take necessary precautions throughout the month. For more detailed information about UV levels and safety measures, check out Chengdu UV Index.

Maximum UV Index Levels in Chengdu for September

The chart shows the monthly maximum UV Index (UVI) for Chengdu 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 Chengdu typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec568101211111011864
Data source: Chengdu 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 Chengdu

As summer's warmth begins to ebb, September in Chengdu greets residents with 214 hours of sunshine—a charming blend of lingering warmth and the anticipation of autumn. This month reflects a gradual transition from the sun-drenched heights of July and August, which boast 285 and 290 hours, respectively. After the peaks of summer, sunshine levels dip, yet September still maintains a robust glow compared to the cooler months ahead. With foliage beginning to change, this period allows for a perfect balance of sunny days sprinkled with the promise of cooler evenings, making it an ideal time for outdoor exploration and enjoying nature's vibrant palette.

Monthly Sunshine Duration in Chengdu: September Highlighted

The September sunshine duration represents the total number of hours Chengdu 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.
JanFebMarAprMayJunJulAugSepOctNovDec188h225h225h236h261h251h285h290h214h165h197h209h
Data source: Chengdu September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Chengdu During September

September in Chengdu, China, marks a brief uptick in sunshine, boasting a 27% chance of sunny weather. This is a slight improvement from the preceding months, where sunshine chances typically linger between 13% and 26%. Although September does not reach the levels of winter months like January and December, which have 44% and 40% chances respectively, the modest increase offers a refreshing break from the summer's grey skies. This transition signals the beginning of autumn, suggesting a more favorable outlook for those eager to bask in the sun once again.

Percentage of Sunny Days in September in Chengdu

The chart illustrates the percentage of sunny days in Chengdu 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 Chengdu experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec44%37%26%19%13%14%26%18%27%14%36%40%
Data source: Chengdu September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Chengdu in September

As September arrives in Chengdu, the city basks in a wholesome 12 hours of daylight, gracefully tapering from the summer's longer days. This slight decrease marks a transition toward autumn, with daylight steadily declining from its peak in June, where it reached 14 hours. Following the summer, both July and August maintain a steady 13 hours, but by September, residents start to feel a gentle shift as daylight begins to retreat. This rhythmic ebb and flow throughout the year not only highlights the city's changing seasons but also invites a period of reflection and preparation for the cozy months ahead. As October approaches, daylight will further shrink to 11 hours, preparing Chengdu for the serene ambiance of fall.

Average Daylight Hours in Chengdu for September

The chart illustrates the variation in daylight duration in Chengdu throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 23m11h 4m11h 59m12h 55m13h 42m14h 5m13h 53m13h 12m12h 19m11h 23m10h 35m10h 10m
Data source: Chengdu daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Chengdu

As September graces Chengdu, a gentle increase in the wind speed to 2.0 m/s (4 mph) heralds a subtle shift from the summer months. This marks the highest average wind speed of the year, hinting at the arrival of autumn and the welcoming of cooler breezes. Throughout the preceding months, the winds have remained relatively calm, hovering around 1.6 to 1.9 m/s (4 mph). However, with September's refreshing gusts, residents can feel a delightful change in the air as nature prepares for the vibrant, crisp days ahead. The gradual decline in wind speeds from earlier months into late autumn reflects a serene transition, yet September stands out as a breath of fresh air, inviting both locals and visitors to embrace the season’s charm.

Average September Wind Speed in Chengdu

The chart displays monthly wind speed patterns in Chengdu, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1.91.81.91.81.81.71.61.82.0 m/s1.61.51.7
Data source: Chengdu September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Chengdu Compares to Other Months

Weather in Chengdu varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Chengdu, 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 minimum of 14°C (57°F) to a maximum of 35°C (95°F), with an average of 22°C (73°F). The month experiences significant rainfall, with 118 mm (4.6 in) of precipitation over 14 days, coupled with high humidity at 92%. In contrast, January brings much cooler temperatures, with a range from -4°C (25°F) to 16°C (62°F) and an average of only 7°C (44°F). This winter month sees minimal precipitation, amounting to just 5 mm (0.2 in) over 1 day, and a slightly lower humidity level of 90%. For a detailed look at January weather, you can visit Chengdu weather in January.

In September, the weather is significantly warmer, with temperatures ranging from a minimum of 14°C (57°F) to a maximum of 35°C (95°F) and an average of 22°C (73°F). This month also sees considerable rainfall, averaging 118 mm (4.6 in) over 14 days, contributing to a humid atmosphere of 92%. In contrast, February presents a much cooler climate, with temperatures dropping to a minimum of -1°C (31°F) and a maximum of 24°C (76°F), averaging around 9°C (48°F). Precipitation is minimal during this month, totaling only 10 mm (0.4 in) over just 2 days, yet the humidity remains high at 92%. For more details, you can check Chengdu weather in February.

September and March exhibit contrasting weather patterns. In September, temperatures range significantly, with minimums around 14°C (57°F) and highs reaching up to 35°C (95°F), resulting in an average of 22°C (73°F). The month is also notably wetter, with 118 mm (4.6 in) of precipitation over 14 days and high humidity at 92%. In contrast, March features cooler temperatures, with a minimum of 4°C (40°F) and a maximum of 30°C (86°F), leading to a more moderate average of 15°C (59°F). Precipitation is much lighter in March, at just 23 mm (0.9 in) over 6 days, along with slightly lower humidity levels of 89%. For detailed insights into March's climate, you can check Chengdu weather in March.

In September, the weather tends to be warmer with average temperatures around 22°C (73°F) and a maximum reaching up to 35°C (95°F), while April sees slightly cooler conditions, with average temperatures of 19°C (66°F) and highs of 36°C (98°F). However, September experiences higher humidity at 92% compared to April's 85%, making those warmer days feel more intense. Precipitation is also more frequent in September, averaging 118 mm (4.6 in) over 14 days, whereas April sees only 58 mm (2.3 in) across 10 days. For more detailed information about April weather in Chengdu, visit Chengdu weather in April.

When comparing the weather in September and May, we notice some distinct differences despite a similar average temperature of 22°C (73°F). September experiences a broader temperature range, with minimums of 14°C (57°F) and maximums reaching up to 35°C (95°F), while May can soar higher, with maximums peaking at 38°C (100°F). Additionally, September sees substantially more rainfall, with 118 mm (4.6 in) of precipitation over about 14 days, compared to May's 74 mm (2.9 in) over 11 days. Humidity levels are also higher in September at 92%, compared to May's 87%, making the former feel a bit more muggy. For more detailed information, you can check out Chengdu weather in May.

When comparing the weather in September and June, several notable differences emerge. In September, temperatures range from a minimum of 14°C (57°F) to a maximum of 35°C (95°F), with an average of 22°C (73°F). This month also sees higher precipitation, totaling 118 mm (4.6 in) over approximately 14 days, and higher humidity at 92%. In contrast, June exhibits slightly warmer temperatures, with minimums of 17°C (63°F), averages of 25°C (78°F), and maximums reaching 36°C (97°F). Additionally, June experiences lower precipitation of 89 mm (3.5 in) over just 9 days and slightly lower humidity at 88%. For detailed insights into the June weather patterns, you can check Chengdu weather in June.

September weather offers slightly cooler temperatures compared to July, with a minimum of 14°C (57°F) and an average of 22°C (73°F), while July sees a minimum of 19°C (66°F) and an average of 27°C (80°F). The maximum temperature in July can reach up to 37°C (98°F), making it the hotter month, whereas September climbs to a maximum of 35°C (95°F). In terms of precipitation, September is somewhat drier with 118 mm (4.6 in) over 14 days, compared to July's heavier rainfall of 312 mm (12.3 in) across 22 days. Humidity levels are similar, with September at 92% and July at 89%. Overall, September acts as a transition to milder conditions after the sweltering July heat. For more detailed information, check Chengdu weather in July.

September weather presents a noticeable shift compared to August. With minimum temperatures dropping to 14°C (57°F) and an average of 22°C (73°F), September feels significantly cooler than August, which boasts minimums of 18°C (64°F) and averages of 27°C (80°F). While September reaches a maximum of 35°C (95°F), August can soar to a blistering 40°C (104°F). Although September experiences about half the precipitation of August—118 mm (4.6 in) compared to 409 mm (16.1 in)—both months share the same high humidity level of 92%. For more details on August weather specifically, you can check Chengdu weather in August.

September tends to be warmer and more humid compared to October, with average temperatures ranging from 14°C (57°F) to a high of 35°C (95°F) and an average of 22°C (73°F). In contrast, October experiences cooler temperatures, with a minimum of 10°C (51°F) and an average high of 30°C (86°F), making it feel much more comfortable. Additionally, September sees higher precipitation totals of 118 mm (4.6 in) over 14 days, while October has significantly lower rainfall of 57 mm (2.3 in) across just 10 days. Both months share a high humidity level of 92%, but the cooler temperatures in October often lead to a more refreshing atmosphere overall. For more detailed insights, check out Chengdu weather in October.

September and November present a striking contrast in weather conditions. In September, temperatures range from a minimum of 14°C (57°F) to a sweltering maximum of 35°C (95°F), with an average of 22°C (73°F). The month also sees considerable rainfall, totaling 118 mm (4.6 in) over 14 days, contributing to high humidity at 92%. In contrast, November offers a much cooler climate, with temperatures dipping to a minimum of 3°C (38°F) and peaking at 24°C (75°F), averaging only 13°C (55°F). Precipitation is significantly reduced to 15 mm (0.6 in) over just 4 days, while the humidity remains constant at 92%. For more detailed insights, check out Chengdu weather in November.

September and December present a stark contrast in weather conditions. In September, temperatures range from a mild 14°C (57°F) to a sweltering 35°C (95°F), with an average of 22°C (73°F). The month also sees significant rainfall, accumulating to 118 mm (4.6 in) over 14 days, and a high humidity level of 92%. On the other hand, December brings a chilly atmosphere, with temperatures dropping to a minimum of -2°C (29°F) and only reaching a maximum of 17°C (63°F), averaging around 7°C (46°F). This winter month is notably drier, with just 11 mm (0.4 in) of precipitation over 3 days and a slight decrease in humidity to 90%. For more detailed information, you can check Chengdu weather in December.

Compare Chengdu's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Chengdu

As September rolls into Chengdu, travelers can expect a notable shift in weather patterns compared to the scorching summer months. The warmth remains, with daytime temperatures still reaching highs, but the evenings cool down pleasantly, offering a welcome reprieve. The increased humidity and frequent rainfall, with over half of the month bringing precipitation, add an element of freshness to the air, making it feel more vibrant than during the hotter tiers of summer. This blend of warmth and moisture sets the stage for a dynamic transition into autumn, striking a balance that is both invigorating and refreshing. For an in-depth look at the city's yearly climate trends, visit Chengdu Climate.