Last updated: August 21, 2025
Shanghai's weather in September presents a dynamic climate, with temperatures ranging from a minimum of 17°C (63°F) to a maximum of 35°C (94°F), averaging around 25°C (78°F). This month marks a transition into fall, but the humidity remains relatively high at 81%, making it feel warmer than it is. Rainfall is also notable, with 177 mm (7.0 in) of precipitation spread across 13 days, ensuring the city stays lush and vibrant. Visitors can expect a mix of sunny days interspersed with occasional showers, creating a unique and robust urban atmosphere.
As summer gives way to autumn, September in Shanghai reveals a delightful shift in temperatures. With a minimum of 17°C (63°F) and a comfortable average of 25°C (78°F), the city sheds the intense summer heat yet maintains a warmth that invites outdoor exploration. The maximum temperature can still reach 35°C (94°F), offering plenty of sunny days for activities along the Bund or in the lush parks. As nature begins to transition, the cooler evenings provide a refreshing respite, making this month a perfect time to experience Shanghai’s vibrant street culture. The gradual cooling trend indicated by September ushers in the fall, setting the stage for the crisp air and colorful foliage that follows in October.
In September, Shanghai experiences a notable shift in its precipitation patterns, receiving 177 mm (7.0 in) of rain over 13 days. This marks a continuation of the wettest months of the year, with the rainfall beginning to taper off from the intense summer deluge, where July recorded the highest levels. Compared to August’s 167 mm, September brings slightly wetter conditions, indicating a persistent humidity even as the summer season wanes. The rainfall contributes to the lush, vibrant landscape of the city, while the average number of rainy days hints at the shifting climate as it transitions towards autumn. This steady precipitation underscores a significant passage from the oppressive summer heat to the cooler, more temperate fall, making September a key month in Shanghai’s meteorological calendar.
As summer's grip begins to loosen in September, Shanghai experiences a notable decrease in humidity, dropping to 81%. This marks a transition from the intensely humid months of July and August, which saw peaks of 93% and 91%, respectively. The trend suggests a gradual easing of moisture in the air, setting the stage for the more temperate conditions of autumn. Following a summer characterized by high humidity, September serves as a refreshing reprieve, leading into the cooler months where humidity levels hover around 80% in October and fluctuate slightly through the remainder of the year. This shift creates a more comfortable climate for outdoor activities, inviting residents and visitors to enjoy the city's vibrant surroundings.
As the summer months transition into September, Shanghai continues to experience intense sun exposure, with the UV Index holding steady at 11, indicating an extreme risk of harm from unprotected sun exposure. This aligns with the peak summer months of June and July, reflecting a consistent trend of high UV levels that demand caution. With a burn time of just 10 minutes, it's crucial for residents and visitors alike to prioritize sun protection during this period. This trend serves as a reminder to stay vigilant against UV rays while enjoying outdoor activities. To learn more about the UV Index and how to protect yourself, check out Shanghai UV Index.
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September in Shanghai brings a delightful transition, basking in an impressive 260 hours of sunshine. As summer wanes, the city retains the warmth felt during the peak months, with sunlight gradually decreasing from August's remarkable 318 hours. This month marks a distinct shift as it precedes October's cooler embrace, which features 245 hours of sunshine. Notably, September holds its own amidst a year marked by escalating daylight hours, especially from January’s modest 157 hours to July's peak 301 hours. As autumn sets in, residents and visitors alike can savor the tail end of summer's glow, making September a vibrant time to experience Shanghai’s charms under a sunlit sky.
As September rolls into Shanghai, the likelihood of sunny weather sees a modest uptick, with a 44% chance of sunshine illuminating the city. This marks a welcome shift from the summer months, where July and June suffer from significantly lower odds of sunny days at 17% and 23%, respectively. While early autumn in Shanghai can still bring some cloud cover, the sunny opportunities are noticeably higher than the peak summer months, hinting at a more favorable climate for outdoor activities. Observing the broader trend, this month serves as a bridge towards more favorable weather, setting the stage for the reliably sunny days that follow in late fall, where the chances climb further to 57% in November and 64% in December.
As summer transitions to autumn, September in Shanghai marks a gentle decline in daylight hours, providing a total of 12 hours of sunlight. This shift reflects the gradual shortening of days that begins in late summer; June's peak of 14 hours gives way to the comforting warmth of early fall. Following a steady descent, October will see daylight drop further to 11 hours. The trend from earlier months, with May and June basking in ample sunlight, highlights the seasonal rhythms that characterize the city's climate. As daylight diminishes, residents can enjoy the softer, golden hues of September evenings, heralding the arrival of a cozy fall ambiance.
As September unfolds in Shanghai, a subtle shift in the air becomes palpable, with an average wind speed of 3.6 m/s (8 mph). While the breezes in the earlier summer months peaked dramatically in July at 5.1 m/s (11 mph), they tend to soften as summer gives way to autumn. This gentle return to steadiness mirrors the city's vibrant transition, trading the warm rush of summer winds for a more temperate zephyr. The winds of September carry a hint of crispness, making it an ideal time for locals and visitors alike to explore the bustling streets and rich culture, all while enjoying the comforting caress of a mild breeze.
Weather in Shanghai varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Shanghai, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather conditions. In September, temperatures range from a mild 17°C (63°F) at night to a scorching 35°C (94°F) during the day, with an average of 25°C (78°F). This month also sees significant rainfall, totaling 177 mm (7.0 inches) over 13 days, accompanied by high humidity at 81%. In contrast, January brings much cooler temperatures, with nighttime lows plummeting to -8°C (19°F) and daytime highs reaching a temperate 22°C (71°F), averaging just 6°C (44°F). Precipitation in January is notably less, at 55 mm (2.2 inches) over only 6 days, and humidity decreases to 70%. For a detailed look at January weather conditions in Shanghai, you can refer to Shanghai weather in January.
September and February present stark contrasts in weather patterns. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 35°C (94°F), with an average of 25°C (78°F), making it a warm month. Additionally, September experiences significant rainfall, totaling 177 mm (7.0 in) over 13 days, coupled with high humidity at 81%. In contrast, February offers a much cooler climate, with temperatures ranging from a frigid -3°C (27°F) to a milder 24°C (76°F), and an average temperature of only 7°C (45°F). Precipitation is noticeably lower in February, with only 60 mm (2.4 in) falling over 8 days and humidity at 73%. For a more detailed look at February conditions, please visit Shanghai weather in February.
In September, the weather is significantly warmer, with average temperatures around 25°C (78°F) and highs reaching up to 35°C (94°F). The month sees considerable rainfall, totaling 177 mm (7.0 in) over 13 days, contributing to a high humidity level of 81%. In contrast, March experiences much cooler temperatures, with an average of only 12°C (54°F) and a maximum of 26°C (79°F). Precipitation in March is also lower, with 83 mm (3.3 in) falling over 12 days, while maintaining the same humidity level of 81%. For more detailed information, you can check out Shanghai weather in March.
September and April showcase contrasting weather patterns. In September, temperatures are notably warmer, with a minimum of 17°C (63°F) and an average of 25°C (78°F), peaking at a maximum of 35°C (94°F). This month also experiences considerable rainfall, with 177 mm (7.0 inches) spread across about 13 days and a humidity level of 81%. In contrast, April offers a much cooler climate, with minimum temperatures of 5°C (42°F), an average of 16°C (61°F), and a maximum reaching 31°C (87°F). Precipitation in April is lighter at 72 mm (2.8 inches) over 9 days, alongside a higher humidity of 87%. For more detailed information, you can check Shanghai weather in April.
September and May present distinct weather patterns, showcasing notable differences in temperature and precipitation. In September, the average temperature is higher at 25°C (78°F), with a minimum of 17°C (63°F) and a maximum reaching 35°C (94°F). This month experiences significant rainfall, accumulating 177 mm (7.0 in) over approximately 13 days, and maintains a humidity level of 81%. In contrast, May is slightly cooler, with an average of 21°C (71°F), ranging from a minimum of 12°C (53°F) to a maximum of 34°C (94°F). It sees less rainfall, totaling 117 mm (4.6 in) over about 10 days, alongside a higher humidity of 87%. For more details about May weather, you can check Shanghai weather in May.
When comparing the weather in September to June, notable differences emerge. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 35°C (94°F), with an average temperature of 25°C (78°F). The month experiences about 177 mm (7.0 in) of rainfall over 13 days, with an average humidity level of 81%. In contrast, June's temperatures are slightly warmer, with a minimum of 18°C (65°F) and a maximum of 36°C (96°F), while maintaining a similar average of 25°C (76°F). Rainfall in June is more abundant at 201 mm (7.9 in) over 15 days, accompanied by higher humidity at 89%. For more detailed insights, check out Shanghai weather in June.
When comparing the weather in September and July, it's evident that July tends to be hotter and more humid. In July, temperatures range from a minimum of 20°C (69°F) to a maximum of 39°C (102°F), with an average of 29°C (84°F) and a high humidity level of 93%. In contrast, September offers a slightly cooler climate, with temperatures from 17°C (63°F) to 35°C (94°F) and an average of 25°C (78°F), alongside a lower humidity of 81%. Precipitation is also more frequent in July, totaling 250 mm (9.8 in) over 16 days, compared to 177 mm (7.0 in) over 13 days in September. For more detailed insights, you can refer to Shanghai weather in July.
September generally offers a slight reprieve from the intense heat of August. While August boasts a higher average temperature of 29°C (85°F) with maximums reaching up to 38°C (100°F), September sees a decrease in average temperature to 25°C (78°F), with maximums maxing out at 35°C (94°F). Notably, September experiences a similar level of precipitation at 177 mm (7.0 in) over 13 days, compared to August's 167 mm (6.6 in) over 15 days. Humidity also drops slightly, from 91% in August to 81% in September, making the latter month feel relatively more comfortable. For a more detailed look, visit Shanghai weather in August.
September weather tends to be significantly warmer than that of October, with average temperatures reaching up to 25°C (78°F) and maximums soaring to 35°C (94°F). In contrast, October sees a drop in temperatures, with averages around 20°C (68°F) and highs peaking at 31°C (89°F). Additionally, September is much wetter, registering 177 mm (7.0 in) of precipitation over 13 days, while October enjoys a drier spell with only 69 mm (2.7 in) of rainfall across just 7 days. Despite the slight decrease in humidity, which hovers around 80% in October compared to 81% in September, the overall weather becomes more comfortable as the month progresses. For more details, you can check Shanghai weather in October.
September and November present contrasting weather experiences. In September, temperatures range from a mild 17°C (63°F) at night to a sweltering high of 35°C (94°F) during the day, with an average of 25°C (78°F). The month is characterized by significant rainfall, accumulating 177 mm (7.0 in) over 13 days, coupled with high humidity of 81%. In stark contrast, November sees a cooler climate with temperatures dropping to a minimum of 2°C (37°F) and averaging around 15°C (59°F), peaking at 27°C (81°F). The precipitation decreases significantly to 51 mm (2.0 in) over just 7 days, while humidity remains relatively steady at 82%. For more details on what to expect during this month, check out Shanghai weather in November.
September and December present starkly different weather conditions. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 35°C (94°F), with an average of 25°C (78°F), creating a warm and humid environment with significant precipitation of 177 mm (7.0 in) over 13 days and humidity levels around 81%. In contrast, December sees a dramatic drop in temperatures, with a minimum of -5°C (22°F) and a maximum of 20°C (69°F), leading to a chillier average of 8°C (47°F). Precipitation is also less frequent, totaling 50 mm (2.0 in) over just 8 days, accompanied by slightly lower humidity at 77%. For more detailed information, check out Shanghai weather in December.
As September rolls into Shanghai, the weather begins to transition from the intense heat of summer to a more moderate and humid climate. While temperatures still reach a maximum of 35°C (94°F), the average temperature settles at a comfortable 25°C (78°F), providing a pleasant reprieve for both residents and visitors alike. However, with 177 mm of precipitation over about 13 days, you'll want to be prepared for occasional rain showers that make this month distinctly different from the drier summer months. The humidity remains high at 81%, enhancing the tropical feel of the city, but it also offers a lush and vibrant atmosphere. For a deeper dive into the overall patterns and nuances of weather in this bustling metropolis, check out Shanghai Climate.