September Weather in Hangzhou, China

Last updated: August 21, 2025

September in Hangzhou, China is characterized by a warm average temperature of 26°C (78°F), with peaks reaching a sizzling 36°C (98°F). As the summer lingers, the city experiences a minimum temperature of 16°C (62°F) during cooler nights. However, it's not all sun, as the month sees about 133 mm (5.2 in) of rainfall over 13 days, contributing to a high humidity level of 81%. Visitors should prepare for a mix of warm weather and occasional showers, making it an ideal time to explore the city's stunning landscapes and rich culture while staying mindful of the changing conditions.

September Temperature in Hangzhou

In September, Hangzhou experiences a delightful transition in temperatures, marking the end of summer and the onset of autumn. With nighttime lows around 16°C (62°F), the air remains comfortably cool, whereas daytime highs can reach up to 36°C (98°F), encouraging outdoor adventures. The average temperature settles at 26°C (78°F), providing a perfect climate for enjoying the city's scenic landscapes. Compared to the sweltering heat of July and August, September offers a refreshing reprieve, as the extreme highs begin to taper off, hinting at the cooler months ahead. As the leaves start to change, this month presents an ideal opportunity to explore Hangzhou’s renowned beauty and rich cultural heritage.

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

The chart illustrates September temperature patterns in Hangzhou, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hangzhou, 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).
JanFebMarAprMayJunJulAugSepOctNovDec434655647378858678685846
Data source: Temperature data for Hangzhou 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 Hangzhou

In September, Hangzhou experiences a noteworthy shift in precipitation patterns as the summer months draw to a close. With an average rainfall of 133 mm (5.2 in) over 13 days, the city sees a moderate decrease from the wetter months of June and July. This month acts as a bridge, heralding the transition into autumn, while still delivering consistent moisture compared to the milder precipitation of the upcoming months. The rainfall in September, though less intense than earlier in the summer, supports the lush landscapes that Hangzhou is renowned for, making it a delightful time for visitors to appreciate the city's natural beauty amidst the gentle rains.

September Precipitation Trends in Hangzhou

The chart displays monthly precipitation patterns in Hangzhou, 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 Hangzhou, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec796811989165348233163133566066
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Hangzhou

In September, Hangzhou experiences a notable shift in humidity, with levels dropping to 81% after the peak summer months. This decrease follows a steady rise from 70% in January to a high of 93% in July, reflecting the region's warm and moist climate. As the summer humidity begins to wane in September, it paves the way for a more comfortable atmosphere, which continues into October with 80% humidity. This cyclical pattern not only marks the transition to autumn but also highlights the high humidity characteristic of Hangzhou’s summer, making September a month of relief and pleasant change.

September Average Humidity in Hangzhou

This chart illustrates the average monthly humidity levels in Hangzhou, 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 Hangzhou is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec70%73%81%87%87%89%93%91%81%80%82%77%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Hangzhou

As September rolls into Hangzhou, the UV Index remains notably high at 10, categorizing it as very high exposure. With a burn time of just 15 minutes, sun protection is crucial for outdoor activities. This slight decline from August's extreme level of 11 suggests a gradual transition towards lower UV exposure as autumn approaches. Nevertheless, the trend shows that for much of the summer and early fall, residents and visitors alike must stay vigilant against harmful rays. For detailed insights, check out the full Hangzhou UV Index.

Maximum UV Index Levels in Hangzhou for September

The chart shows the monthly maximum UV Index (UVI) for Hangzhou 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 Hangzhou typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec569101111111110864
Data source: Hangzhou 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 Hangzhou

As summer transitions into autumn, September in Hangzhou sees a gentle decline in sunshine hours, with 243 hours of sunlight gracing the city—a noticeable drop from the sun-soaked 312 hours of August. This shift signals the end of peak summer brightness, yet it remains significantly brighter than the winter months ahead. Throughout the year, there is a clear upward trend from January to August as the city basks in increasing daylight, peaking in mid-summer. Following September, the sunshine hours gradually taper off, hinting at the cooler, shorter days of autumn and winter, yet each month maintains a vibrant glow compared to the initial cold months of the year.

Monthly Sunshine Duration in Hangzhou: September Highlighted

The September sunshine duration represents the total number of hours Hangzhou 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.
JanFebMarAprMayJunJulAugSepOctNovDec142h195h210h249h273h247h285h312h243h227h214h210h
Data source: Hangzhou September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Hangzhou During September

In Hangzhou, China, September stands out with a 44% chance of sunny weather, making it one of the more favorable months for sunshine after a long summer of low sun probabilities. As temperatures start to cool down from the sweltering days of July and August, when the likelihood of clear skies dips to 15% and 30% respectively, September offers a refreshing contrast. This transition month not only hints at an increase in sunny days but also paves the way for a brighter outlook as autumn approaches, with November seeing an even higher 46% chance. With September’s blend of warmth and sun, it’s an ideal time to explore the natural beauty of Hangzhou.

Percentage of Sunny Days in September in Hangzhou

The chart illustrates the percentage of sunny days in Hangzhou 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 Hangzhou experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec51%38%26%31%27%19%15%30%44%39%46%65%
Data source: Hangzhou September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Hangzhou in September

As summer gracefully transitions into autumn, September in Hangzhou, China offers a delightful shift in daylight hours, bringing about 12 hours of sunlight. Following the peak of 14 hours in June, the days begin to shorten, with daylight tapering off slightly through July and August. This gentle decrease continues as October approaches, where daylight dips to 11 hours, hinting at the inevitable arrival of winter. The shifting light patterns not only signal the change of seasons but also invite residents and visitors alike to enjoy the varied activities and natural beauty that each phase brings, from vibrant late-summer sunsets to the crisp air of early autumn.

Average Daylight Hours in Hangzhou for September

The chart illustrates the variation in daylight duration in Hangzhou throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 25m11h 6m11h 59m12h 54m13h 40m14h 2m13h 51m13h 11m12h 19m11h 24m10h 37m10h 13m
Data source: Hangzhou daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Hangzhou

In September, the winds of Hangzhou begin to stir gently, averaging around 2.4 m/s (5 mph). This marks a slight increase from the summer months, where July experiences a noticeable peak at 3.2 m/s (7 mph), suggesting a shift towards a more moderate breeze as autumn approaches. The earlier lush summer air gives way to a soft, refreshing wind, contributing to the city's tranquil atmosphere. Interestingly, September's wind speed is slightly higher than the quieter months of June and August, which both reported 2.0 m/s (4 mph). This transitional period not only heralds the onset of cooler temperatures but also infuses Hangzhou with a renewed sense of vitality, as the wind whispers tales of the changing season. The overall trend reveals a decrease in wind speed during the peak summer months, followed by a gentle resurgence as fall begins to embrace the landscape, enhancing the charm of this picturesque city.

Average September Wind Speed in Hangzhou

The chart displays monthly wind speed patterns in Hangzhou, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.52.52.52.52.32.03.22.02.4 m/s2.62.42.3
Data source: Hangzhou September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Hangzhou Compares to Other Months

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

In September, the weather is notably warm, with temperatures ranging from a minimum of 16°C (62°F) to a maximum of 36°C (98°F), averaging around 26°C (78°F). The month experiences significant precipitation, totaling 133 mm (5.2 in) across approximately 13 days, accompanied by a high humidity level of 81%. In contrast, January presents a starkly different climate. Temperatures drop significantly, with lows of -9°C (16°F) and a maximum of 24°C (75°F), averaging just 6°C (43°F). Additionally, January sees less rainfall, with a total of 79 mm (3.1 in) over 9 days, and humidity levels are lower at 70%. For a detailed look at the weather in January, check out Hangzhou weather in January.

September weather is characterized by warm temperatures, with a minimum of 16°C (62°F) and an average of 26°C (78°F), reaching highs of up to 36°C (98°F). The month is also marked by significant rainfall, totaling 133 mm (5.2 in) over 13 days, and a high humidity level of 81%. In stark contrast, February is much cooler, with temperatures ranging from a minimum of -4°C (25°F) to an average of 8°C (46°F) and a maximum of 27°C (80°F). February experiences less precipitation, accumulating 68 mm (2.7 in) over 9 days, and has a lower humidity of 73%. For a detailed look at February weather in Hangzhou, you can visit Hangzhou weather in February.

September and March present contrasting weather patterns, reflecting the transition between seasons. In September, temperatures range from a minimum of 16°C (62°F) to a maximum of 36°C (98°F), with an average of 26°C (78°F), making it a warm month. The humidity remains high at 81%, accompanied by 133 mm (5.2 in) of precipitation over 13 days. In contrast, March experiences much cooler temperatures, ranging from a minimum of 2°C (35°F) to a maximum of 29°C (85°F), with an average of just 13°C (56°F). Although March has a slightly lower total precipitation of 119 mm (4.7 in) spread over 14 days, humidity levels remain consistent at 81%. For a more detailed look at March weather, visit Hangzhou weather in March.

September and April present contrasting weather patterns. In September, temperatures range from a minimum of 16°C (62°F) to a scorching maximum of 36°C (98°F), with an average of 26°C (78°F). The month sees considerable rainfall, with 133 mm (5.2 in) spread over 13 days and humidity averaging 81%. In contrast, April is significantly cooler, with temperatures dropping to a minimum of 4°C (40°F) and reaching a maximum of 34°C (94°F), but with an average of only 18°C (64°F). April experiences less precipitation at 89 mm (3.5 in) over 10 days, coupled with slightly higher humidity at 87%. For more detailed information, you can check Hangzhou weather in April.

In comparing the weather of September and May, we see some notable differences and similarities. September experiences warmer temperatures with a minimum of 16°C (62°F) and an average of 26°C (78°F), while May starts cooler with a minimum of 11°C (52°F) and an average of 23°C (73°F). However, May boasts the highest maximum temperature of 38°C (101°F), which surpasses September's peak of 36°C (98°F). Precipitation in May is also slightly higher at 165 mm (6.5 in) compared to September's 133 mm (5.2 in), though both months have a comparable number of rainy days, with May averaging 12 days and September 13 days. Additionally, humidity levels are higher in May at 87%, compared to 81% in September, contributing to a more muggy feel during that time. For more detailed insights, you can check out Hangzhou weather in May.

In comparing the weather between September and June, we see that both months have warm temperatures, but June tends to be slightly hotter with a maximum temperature reaching 37°C (99°F) compared to September's peak of 36°C (98°F). The average temperatures are also quite similar, with June averaging 25°C (78°F) and September at 26°C (78°F), but September experiences a bit less humidity at 81% versus June's higher 89%. Rainfall is significantly higher in June, accumulating 348 mm (13.7 in) over 18 days, while September receives 133 mm (5.2 in) across 13 days, indicating a wetter month in June. For a more detailed look at June weather, you can check out Hangzhou weather in June.

When comparing the weather in September to that of July, notable differences emerge. September showcases milder temperatures, with a minimum of 16°C (62°F) and an average of 26°C (78°F), while July boasts higher temperatures, including a minimum of 22°C (71°F) and an average of 29°C (85°F). Additionally, July experiences more intense heat, peaking at 41°C (106°F), compared to September's maximum of 36°C (98°F).

In terms of precipitation, July also has a higher rainfall total of 233 mm (9.2 in) over 17 days, whereas September sees 133 mm (5.2 in) across 13 days. The humidity levels in both months are relatively high, with July at 93% and September at 81%. For more detailed insights about the climate in July, you can visit Hangzhou weather in July.

In September, the weather tends to cool slightly compared to August. The minimum temperature drops to 16°C (62°F), with an average of 26°C (78°F) and a maximum of 36°C (98°F), while August enjoys a warmer minimum of 18°C (65°F) and an average of 30°C (86°F), peaking at 40°C (103°F). Both months experience significant rainfall, with September receiving 133 mm (5.2 in) over 13 days, compared to August's 163 mm (6.4 in) over 14 days. Humidity levels are also higher in August at 91%, whereas September sees a slightly lower humidity at 81%. For a more detailed look at the conditions in August, check out Hangzhou weather in August.

September typically experiences warmer temperatures, with an average of 26°C (78°F) and highs reaching up to 36°C (98°F), whereas October sees a significant drop, with average temperatures falling to 20°C (68°F) and a maximum of 35°C (95°F). Additionally, September is marked by higher rainfall, accumulating 133 mm (5.2 in) over 13 days, compared to October's more moderate precipitation of 56 mm (2.2 in) over just 6 days. Humidity levels remain relatively stable between the two months, with September at 81% and October at 80%. For more details about the weather in October, you can check Hangzhou weather in October.

September and November exhibit notable differences in weather patterns. September tends to be much warmer, with average temperatures around 26°C (78°F) and maximums reaching up to 36°C (98°F). In contrast, November sees a significant drop in temperatures, with averages around 14°C (58°F) and maximums of 31°C (89°F), showcasing a cooler climate. Precipitation is also more abundant in September, totaling 133 mm (5.2 in) over 13 days, compared to just 60 mm (2.4 in) across 9 days in November. Interestingly, humidity levels remain relatively similar, hovering around 81% in September and 82% in November. For more detailed information, you can check Hangzhou weather in November.

In September, the weather is typically warm, with temperatures ranging from a pleasant minimum of 16°C (62°F) to a scorching maximum of 36°C (98°F). This month also sees significant precipitation, averaging 133 mm (5.2 in) over about 13 days, and high humidity levels at 81%. In contrast, December brings a dramatic change, with much cooler temperatures that range from a low of -4°C (25°F) to a high of 23°C (74°F), averaging around 8°C (47°F). Rainfall decreases to 66 mm (2.6 in) over just 8 days, and humidity dips slightly to 77%. For more information on December weather conditions in the region, you can visit Hangzhou weather in December.

Compare Hangzhou's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Hangzhou

September in Hangzhou ushers in a transition of seasons, characterized by warmer days and cooler nights. As summer's heat lingers, temperatures can peak impressively while maintaining a pleasant average. However, the month also brings increased precipitation, with nearly half the month experiencing rain, contributing to the city's lush landscapes. The high humidity can make the air feel thicker, setting it apart from the drier winter months. Overall, September serves as a vibrant bridge to autumn, offering a unique blend of warmth and moisture. For more insights on the climate throughout the year, visit Hangzhou Climate.