Last updated: August 21, 2025
September in Nanjing, China is characterized by a warm climate that showcases maximum temperatures soaring to 38°C (100°F), with an average around 26°C (79°F) and cooler nights dropping to 17°C (63°F). Throughout the month, the city experiences 108 mm (4.3 in) of precipitation across approximately 15 days, contributing to a humidity level of 62%. This blend of warmth and moisture sets the stage for a vibrant transition into autumn, making it an ideal time to explore the city’s rich cultural heritage while enjoying the lingering summer atmosphere.
In September, Nanjing begins to transition from the intense summer heat to a more moderate climate, yet it still experiences warm temperatures. The average temperature hovers around 26°C (79°F), with daytime highs reaching up to 38°C (100°F), offering a final taste of summer warmth. As the month progresses, the minimum temperatures drop to 17°C (63°F), signaling the approach of autumn. This month marks a shift as humidity begins to wane, making the weather feel more comfortable, while still retaining the lingering warmth of the preceding months. Overall, September presents a blend of summer warmth and the refreshing hints of fall, perfect for outdoor activities and exploring the vibrant city of Nanjing.
In September, Nanjing experiences a notable transition as precipitation shifts to a more moderate level, amounting to 108 mm (4.3 in) over 15 days of rain. This decline from the stormy summer months, particularly June, with its hefty 258 mm (10.1 in), marks a gradual easing into autumn. However, September still retains a fair share of rainfall, ensuring that the city remains lush and vibrant. As the year progresses, the precipitation levels dip further, with October showcasing a striking reduction to 50 mm (2.0 in). This trend underscores a seasonal pattern in Nanjing's climate, characterized by wetter summers giving way to drier, cooler months, illustrating the rhythmic ebb and flow of the region’s weather.
As the summer months wane, September in Nanjing, China, brings a noticeable shift in humidity levels, dipping to 62%. This decrease marks a welcome reprieve from the sweltering, high-humidity peaks of July and August, which hover around 89% and 88%, respectively. The transition continues into the fall, with October experiencing even lower humidity at 56%. Overall, while September retains a bit of summer's humidity, it sets the stage for drier and more comfortable conditions that characterize the coming months. This trend highlights the natural ebb and flow of humidity in Nanjing, showcasing the region's distinct seasonal shifts.
In September, Nanjing continues to experience an exceptionally high level of UV exposure, with a UV Index of 12, categorized as extreme. This marks a gradual decline from the peak summer months, where the Index soared to 13, yet still requires vigilant sun protection, as the burn time remains a swift 10 minutes. As the season transitions into autumn, residents and visitors should remain aware of these significant UV levels, particularly following the intense summer. Ensuring proper sun safety measures during this time is essential to protect skin from potential damage. For more detailed information, check out the Nanjing UV Index.
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As summer gracefully transitions into autumn, September in Nanjing offers an impressive 286 hours of sunshine, making it a delightful time of year. This month stands out distinctly, following the sun-drenched peak of July with its remarkable 311 hours, and August, which closely follows with 309 hours. The consistent warmth of late summer keeps the days bright, inviting locals and visitors alike to soak up the sun before the cooler months arrive. Compared to the earlier months of the year, such as January with just 196 hours, September shines as a vibrant reminder of the lingering summer glow, paving the way for the beautifully mild autumn days ahead.
In September, Nanjing, China sees a 53% chance of sunny weather, marking a significant recovery from the low sunlight during the summer months. This month is a turning point, as the likelihood of sunny days begins to rise from the damp, overcast conditions often experienced in July and August. Following an overall pattern, September's sun is reminiscent of early spring, where chances hover around a healthy average, setting the stage for a transition into milder autumn. As days get shorter and temperatures cool, residents and visitors alike can look forward to a delightful blend of sunshine and refreshing breezes, making it an ideal time for outdoor activities and exploration.
In Nanjing, China, the month of September marks a noteworthy transition in daylight duration, where the days decrease from the summer peaks of July and August. With approximately 12 hours of daylight, September stands in line with the preceding months of March, April, and May, signaling the end of the longer summer days. As autumn approaches, daylight hours gradually begin to wane, setting the stage for the shorter days of October and November. This trend highlights the rhythmic shift of seasons in Nanjing, where daylight ebbs and flows, reflecting the delicate balance between summer's brightness and winter's embrace.
As the summer heat wanes, September in Nanjing greets residents with a gentle breeze, averaging just 1.5 m/s (3 mph)—the calmest wind speed of the year. This tranquil atmosphere contrasts with the slightly stronger winds of earlier months, hinting at the transition to autumn. The decline from the peak summer gusts of 2.3 m/s (5 mph) in May to September's soft whispers beautifully encapsulates the city's gradual shift, creating an ideal backdrop for leisurely strolls and outdoor gatherings. As October approaches, the winds will pick up again, signaling the invigorating changes of fall to come.
Weather in Nanjing varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Nanjing, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present contrasting weather patterns. In September, temperatures range from a mild 17°C (63°F) to a scorching 38°C (100°F), with an average of 26°C (79°F). This month typically experiences considerable precipitation, with about 108 mm (4.3 in) falling over 15 days, contributing to a humidity level of 62%. In stark contrast, January offers a much cooler climate, with temperatures fluctuating between a low of -2°C (29°F) and a maximum of 26°C (78°F), resulting in a much lower average of 10°C (50°F). Precipitation drops significantly to 43 mm (1.7 in) over just 6 days, while humidity remains relatively stable at 63%. For more detailed insights into January weather, you can visit Nanjing weather in January.
In September, the weather is characterized by warm temperatures, with a minimum of 17°C (63°F), average highs around 26°C (79°F), and peaks reaching up to 38°C (100°F). The month is relatively wet, receiving 108 mm (4.3 in) of precipitation spread over 15 days, while humidity sits at a comfortable 62%. In contrast, February sees a significant drop in temperatures, with a minimum of -2°C (29°F) and an average temperature of only 11°C (52°F); however, it can still reach a maximum of 28°C (82°F). February experiences less rainfall, totaling 82 mm (3.2 in) over 9 days, and a slightly higher humidity level of 66%. For more detailed information, you can check Nanjing weather in February.
When comparing the weather in September and March, it’s evident that both months offer distinct experiences. September is characterized by warm temperatures, with averages around 26°C (79°F) and maximums reaching up to 38°C (100°F). In contrast, March experiences much cooler weather, with average temperatures of 16°C (61°F) and maximums peaking at 30°C (87°F).
Precipitation levels also differ, as September sees about 108 mm (4.3 in) over 15 days, while March is wetter, receiving 162 mm (6.4 in) over 17 days. Additionally, March boasts higher humidity at 77%, compared to September's 62%. For those interested in more details about March weather specifically, please refer to Nanjing weather in March.
September and April present contrasting weather patterns, reflecting the transition from summer to autumn and winter to spring, respectively. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 38°C (100°F), with an average of 26°C (79°F). This month experiences around 108 mm (4.3 in) of precipitation over about 15 days, accompanied by a humidity level of 62%. In contrast, April sees cooler temperatures, where the minimum is 7°C (45°F) and the maximum reaches 31°C (88°F), with an average of 19°C (67°F). April is wetter, with 168 mm (6.6 in) of precipitation over 17 days and a higher humidity of 73%. For more detailed insights about April weather, check out Nanjing weather in April.
In September, the weather tends to be quite warm, with average temperatures ranging from a minimum of 17°C (63°F) to a peak of 38°C (100°F), while experiencing relatively moderate humidity at 62%. Comparatively, May is cooler, showcasing a lower average temperature range from 11°C (53°F) to 34°C (94°F), but it comes with higher humidity levels at 85%. Moreover, May is characterized by heavier rainfall, with a total of 171 mm (6.7 in) over approximately 19 days, compared to September’s 108 mm (4.3 in) across 15 days. For a detailed look at May's weather specifics, you can check Nanjing weather in May.
September and June present distinct differences in weather patterns. While both months share an average temperature of 26°C (79°F), September typically experiences a wider temperature range, with minimums of 17°C (63°F) and maximums hitting up to 38°C (100°F). In contrast, June has a slightly warmer minimum temperature of 18°C (64°F) and a lower maximum of 34°C (94°F).
Moreover, June is much wetter, with a notable precipitation of 258 mm (10.1 in) over 21 days, compared to September's 108 mm (4.3 in) over 15 days. The humidity levels are also higher in June at 83%, compared to September's 62%. These variations highlight how September starts to transition into drier and hotter conditions, while June remains characterized by higher humidity and rainfall. For more details, check out Nanjing weather in June.
When comparing the weather between September and July, notable differences emerge in temperature, precipitation, and humidity. September typically sees a minimum temperature of 17°C (63°F) and an average of 26°C (79°F), with a maximum of 38°C (100°F). In contrast, July offers warmer conditions, with minimums around 21°C (70°F), an average of 28°C (83°F), and a peak of 39°C (103°F).
In terms of precipitation, September receives about 108 mm (4.3 inches) over 15 days, while July has slightly less at 98 mm (3.9 inches) across 16 days. Humidity is also higher in July, averaging 89%, compared to September's 62%. For more detailed insights, check out Nanjing weather in July.
September weather sees a noticeable shift compared to August, with lower minimum temperatures of 17°C (63°F) compared to 22°C (71°F) in August. The average temperature drops slightly to 26°C (79°F), while August maintains a warmer average of 28°C (82°F). However, both months experience maximum temperatures reaching up to 38°C (100°F). Precipitation levels decrease in September to 108 mm (4.3 in) over 15 days, in contrast to August's higher precipitation of 152 mm (6.0 in) across 20 days. Additionally, humidity in September is lower at 62%, compared to the more humid conditions of 88% in August. For more detailed weather insights, check Nanjing weather in August.
In comparing September and October weather, September presents warmer temperatures, with a minimum of 17°C (63°F) and an average reaching up to 26°C (79°F), while October sees a drop in temperatures with a minimum of 11°C (52°F) and an average of 21°C (70°F). Additionally, September experiences more rainfall, totaling 108 mm (4.3 in) over 15 days, compared to October's substantially drier conditions, which only accumulate 50 mm (2.0 in) over 6 days. Humidity also decreases slightly from September's 62% to October's 56%, making October a more comfortable month overall. For more detailed insights, you can check Nanjing weather in October.
September and November present strikingly different weather conditions. In September, temperatures can soar, with a minimum of 17°C (63°F), an average of 26°C (79°F), and a maximum reaching up to 38°C (100°F). This month also experiences significant rainfall, accumulating 108 mm (4.3 in) over about 15 days, while humidity hovers around 62%. In contrast, November sees a notable drop in temperature, with a minimum of 5°C (42°F), an average of 16°C (62°F), and a maximum of 30°C (87°F). Precipitation decreases to 45 mm (1.8 in) over just 8 days, and the humidity remains fairly steady at 63%. For a detailed look at what to expect, check out Nanjing weather in November.
In comparing the weather conditions of September and December, a notable shift is observed. September experiences warmer temperatures, with a minimum of 17°C (63°F) and an average of 26°C (79°F), reaching highs of up to 38°C (100°F). However, it is also characterized by higher precipitation, with 108 mm (4.3 in) falling over 15 days, resulting in moderate humidity levels of 62%. In contrast, December ushers in a cooler climate, where temperatures drop significantly, with a minimum of 0°C (32°F) and an average of 11°C (52°F), peaking at a milder 26°C (79°F). December also sees decreased rainfall, totaling just 31 mm (1.2 in) over 5 days, despite a slightly higher humidity of 70%. For more detailed insights, check Nanjing weather in December.
As September rolls into Nanjing, the weather undergoes a noticeable transformation, marking the transition from the sweltering summer to a more temperate climate. While temperatures can still soar to maximums around 38°C (100°F), the average drops to a more comfortable 26°C (79°F), providing a reprieve from the intense heat of the previous months. With humidity levels around 62%, it feels less oppressive, although occasional rain does contribute to an average precipitation of 108 mm over about 15 days. This blend of warmth and moisture creates an inviting atmosphere for both locals and travelers, paving the way for the vibrant autumn months. For more insights on how September fits into the overall climate, be sure to check out Nanjing Climate.