Last updated: August 21, 2025
September in Haikou, China experiences a dynamic blend of warm temperatures and notable humidity. With maximum highs reaching 37°C (99°F), the month balances an average temperature of 25°C (77°F), while dipping to a minimum of 15°C (59°F). Rainfall is frequent, contributing to a total precipitation of 98 mm (3.9 in) over 12 days, creating a lush atmosphere typical of this subtropical region. Expect humidity levels around 72%, adding to the vibrant tropical feel that characterizes Haikou during this time.
In September, Haikou experiences a delightful transition as temperatures begin to cool slightly from the summer heat. With minimums around 15°C (59°F) and average highs hitting 37°C (99°F), the city remains warm and inviting for outdoor activities. The overall average temperature sits at a comfortable 25°C (77°F), making it a perfect time to explore the beautiful coastal scenery. The trend shows that while the days are still predominantly warm, the gradual drop in temperatures signals the onset of autumn, providing a refreshing contrast to the preceding sweltering months of July and August.
In September, Haikou experiences a notable shift in precipitation, with 98 mm (3.9 in) of rain falling over 12 days. This marks a decrease compared to the heavier downpours of the summer months, particularly June, which sees a peak rainfall of 309 mm (12.1 in). As the wet season begins to wane, September's rainfall is indicative of a transition towards drier conditions, hinting at the approaching autumn. With the stormy intensity of summer storms mellowing, the city's lush landscapes continue to thrive, benefiting from the remnants of the tropical monsoon influences while paving the way for more stable weather into October.
In September, Haikou experiences a noticeable decline in humidity, dipping to 72% after the sweltering heights of summer. This reduction marks a transition from the peak humidity levels of July, which can reach an impressive 91%. Following the humid months of April through August, where figures hover between 86% and 91%, September offers a brief respite, making it a more comfortable time for outdoor activities. As the month progresses, humidity levels gradually increase again, setting the stage for the slightly higher averages of October and November. Overall, September serves as a pivotal moment in Haikou's climatological rhythm, balancing the lingering warmth of summer with hints of the approaching autumn.
In September, Haikou experiences a notably high UV Index of 11, categorized as extreme, which indicates a continuous need for sun protection. This slight decrease from the summer months, where the UV Index peaks at 12, still presents significant risks for sunburn with a burn time of just 10 minutes. As the year transitions into the cooler months, the UV levels begin to taper off, yet September remains a crucial month for awareness and protection. Visitors and locals alike should prepare accordingly and heed advice on sun safety to enjoy the tropical climate while minimizing skin damage. For more detailed information on UV levels throughout the year, check out Haikou UV Index.
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As September unfolds in Haikou, China, the city basks in an impressive 241 hours of sunshine, reflecting a transition from the peak summer brightness of August, which recorded a remarkable 294 hours. The month stands out as a bridge between the sweltering summer days and the milder autumn, with sunlight gradually tapering off as the year progresses. Following the sunny crescendo of August, September retains a vibrant glow, outshining the earlier months of the year while hinting at the softer light of October's 209 hours. This trend of abundant sunshine not only enhances the city's picturesque landscapes but also invites outdoor activities, making September a delightful time to experience Haikou's charm.
In Haikou, China, the likelihood of experiencing sunny weather sees a notable shift as September rolls in, with the chance of sun reaching 39%. This marks a significant improvement compared to the dreary summer months, where the probabilities plummet to as low as 11% in July and 12% in June. As the city transitions into autumn, sun-seekers can expect clearer skies than in the sweltering summer, though the sunshine is still less prevalent than in the cooler months of January and December, when sunny chances are 53% and 50%, respectively. Ultimately, September offers a refreshing reprieve from the relentless rain, making it a potentially delightful time for outdoor activities in Haikou.
In September, Haikou enjoys a delightful 12 hours of daylight, offering a beautiful transition from the summer months. This slight decrease in daylight compared to the 13 hours experienced during the peak of summer reflects the gradual shift towards autumn. The city typically sees an increase in daylight hours from January to May, peaking in late spring before gradually tapering off. As the year progresses, October will bring another reduction to 11 hours, followed by a return to shorter days in the cooler months of late fall and winter. This rhythmic pattern of daylight highlights Haikou's dynamic seasonal changes, enhancing the vibrant tapestry of life in this coastal city.
In September, Haikou experiences a gentle breeze, with an average wind speed of 1.5 m/s (3 mph), which maintains the trend of softer winds prevalent in the summer months. As the year progresses, wind speeds in Haikou reveal a modest fluctuation; the transition from peak summer winds in July, where speeds reach up to 1.8 m/s (4 mph), gradually gives way to calmer conditions in August and September. Interestingly, while the wind might seem subdued, it plays a vital role in tempering the tropical heat, offering a refreshing touch as the city prepares for the cooler months ahead. Overall, September stands out as a month where intimacy with the breeze lingers lightly, embodying the serene charm of Haikou's coastal allure.
Weather in Haikou varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Haikou, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase dramatically contrasting weather patterns. In September, temperatures typically range from a minimum of 15°C (59°F) to a sweltering maximum of 37°C (99°F), with an average of 25°C (77°F). The month experiences higher humidity at 72% and notable precipitation of 98 mm (3.9 in) spread over 12 days. Conversely, January brings much cooler conditions, with temperatures dipping to a minimum of -5°C (24°F) and averaging around 8°C (46°F). The maximum temperature reaches a pleasant 26°C (79°F), but the month sees significantly less rainfall at 44 mm (1.7 in) over just 7 days and lower humidity at 65%. For a closer look at January weather conditions, check out Haikou weather in January.
September and February showcase stark contrasts in weather. September typically experiences milder temperatures, ranging from a minimum of 15°C (59°F) to a high of 37°C (99°F), with an average of 25°C (77°F). This month also sees considerable rainfall, with about 98 mm (3.9 in) of precipitation over 12 days and a humidity level of 72%. In contrast, February is much cooler, featuring temperatures that can drop as low as -5°C (22°F) and reach a maximum of 28°C (82°F), averaging at 9°C (48°F). The precipitation in February is lower, with about 65 mm (2.6 in) spread over 9 days, while humidity remains relatively constant at 71%. For more specific insights on February weather in Haikou, you can visit Haikou weather in February.
In September, the weather is generally warmer, with average temperatures around 25°C (77°F) and highs reaching up to 37°C (99°F), while humidity levels sit at 72%. This month experiences about 98 mm (3.9 in) of rainfall over approximately 12 days. In contrast, March brings cooler temperatures, averaging 13°C (56°F) with maximums reaching 31°C (88°F) and minimums dropping to 0°C (33°F). Additionally, March has a higher precipitation level of 122 mm (4.8 in) spread over 15 days, coupled with increased humidity at 81%. For more detailed weather specifics, you can check Haikou weather in March.
In comparing the weather of September and April, it's clear that September typically experiences warmer temperatures, with an average reaching 25°C (77°F) and highs hitting 37°C (99°F), while April is cooler, averaging 17°C (63°F) with a maximum of 33°C (92°F). Both months see similar levels of precipitation, with September receiving 98 mm (3.9 in) over 12 days and April slightly less at 97 mm (3.8 in) over 13 days. Additionally, humidity is higher in April at 86%, compared to September's 72%, contributing to a more temperate feel in the spring. For more detailed information, you can check Haikou weather in April.
When comparing the weather in September and May, notable differences emerge. In September, temperatures range from a minimum of 15°C (59°F) to a maximum of 37°C (99°F), with an average of 25°C (77°F). This month experiences around 98 mm (3.9 in) of precipitation over approximately 12 days and boasts a humidity level of 72%. Conversely, May tends to be slightly cooler, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 39°C (103°F) and an average of 22°C (71°F). However, May is considerably wetter, with total precipitation reaching 207 mm (8.2 in) over about 15 days and higher humidity at 87%. For more specifics on May weather, visit Haikou weather in May.
In comparing the weather between September and June, both months demonstrate a similar temperature range, with minimums of 15°C (59°F), average temperatures around 25°C (77°F), and maximums reaching up to 37°C (99°F). However, June is significantly wetter, receiving 309 mm (12.1 in) of precipitation over 20 days, compared to September's 98 mm (3.9 in) over only 12 days. Additionally, June features higher humidity levels at 87%, while September is somewhat drier with a humidity of 72%. For a detailed look at the weather patterns in June, you can check the following link: Haikou weather in June.
In comparing the weather between September and July, we see notable differences in temperature and precipitation. September's temperatures range from a minimum of 15°C (59°F) to a maximum of 37°C (99°F), with an average of 25°C (77°F). In contrast, July typically experiences higher temperatures, with a minimum of 20°C (69°F) and an average of 28°C (82°F), peaking at 37°C (100°F).
Precipitation levels in July are significantly higher, with 199 mm (7.9 in) across 18 days, compared to September's 98 mm (3.9 in) over just 12 days. Additionally, July's humidity is notably higher at 91%, whereas September has a humidity level of 72%. For more detailed information, you can check the Haikou weather in July.
In comparing the weather trends of September and August, September generally experiences a slightly cooler daytime average, with temperatures ranging from a minimum of 15°C (59°F) to a maximum of 37°C (99°F), while August showcases warmer conditions with minimums around 21°C (70°F) and maximums peaking at 38°C (100°F). Additionally, September sees a decrease in precipitation, marking 98 mm (3.9 in) over 12 days, compared to August's heavier rainfall of 159 mm (6.3 in) across 17 days. Humidity levels also drop in September to 72%, compared to the more humid August climate, which averages at 87%. For a detailed look at August weather patterns, you can check Haikou weather in August.
September weather is characterized by higher temperatures, with minimums around 15°C (59°F) and average highs reaching up to 37°C (99°F). The month also experiences significant rainfall, totaling 98 mm (3.9 in) over 12 days, and humidity levels hover around 72%. In contrast, October sees a notable drop in temperatures, with minimums dipping to 8°C (47°F) and average highs averaging 35°C (96°F). Precipitation decreases to 66 mm (2.6 in) over just 7 days, and humidity rises slightly to 74%. For more detailed insights, check out Haikou weather in October.
September weather is characterized by warm temperatures, with a minimum of 15°C (59°F) and an average high of 25°C (77°F) that can peak at a scorching 37°C (99°F). It also experiences higher precipitation, averaging 98 mm (3.9 in) over approximately 12 days, along with a humidity level of 72%. In contrast, November sees a significant drop in temperatures, with a minimum of 2°C (36°F) and an average of 14°C (58°F), while maximum temperatures reach a more moderate 31°C (88°F). Rainfall decreases to 64 mm (2.5 in) across 8 days, accompanied by slightly higher humidity at 80%. For a more detailed look at what to expect, check out Haikou weather in November.
In September, temperatures in Haikou are significantly warmer, with a minimum of 15°C (59°F) and a maximum that can reach up to 37°C (99°F), averaging around 25°C (77°F). The month also experiences considerable rainfall, with 98 mm (3.9 in) over approximately 12 days, paired with a humidity level of 72%. In contrast, December brings much cooler weather, characterized by a minimum temperature of -2°C (28°F) and a maximum of 28°C (83°F), averaging just 9°C (48°F). Precipitation drops to 38 mm (1.5 in) over 8 days, and humidity slightly increases to 78%. For more detailed information, you can visit Haikou weather in December.
As September unfolds in Haikou, the weather transitions into a more moderate yet still warm atmosphere, offering a welcome respite from the sweltering summer heat. With average temperatures hovering around 25°C (77°F), this month presents a perfect blend of warmth and comfort. While the potential for rain increases with 98 mm of precipitation spread over 12 days, the humidity remains a notable factor at 72%, making the air feel more humid than earlier months. This shift towards a slightly wetter and cooler climate signals the gradual approach to fall, providing an ideal setting for outdoor activities amidst lush green surroundings. For a deeper dive into the nuances of weather patterns in Haikou, visit Haikou Climate.