Last updated: August 21, 2025
In Haikou, China, September brings a warm and humid climate, with average temperatures hovering around 27°C (80°F). The month's peak temperatures can soar to a scorching 38°C (101°F), while the cooler nights dip to a pleasant 17°C (63°F). Travelers can expect about 71 mm (2.8 in) of rainfall spread over 9 rainy days, contributing to the area's lush greenery. With humidity levels around 72%, September in Haikou offers a tropical ambiance that invites both exploration and relaxation.
As September rolls into Haikou, the city experiences a noticeable shift in temperatures, marking the transition from the scorching summer months to the slightly cooler fall. With minimum temperatures averaging around 17°C (63°F) and maximums peaking at a steamy 38°C (101°F), residents can expect warm days, though the average temperature settles at a comfortable 27°C (80°F). This month is characterized by lingering heat, reminiscent of August, but with a hint of relief that foreshadows the pleasant autumn ahead. The gradual decline in nighttime temperatures also suggests that fall is on the horizon, inviting outdoor gatherings and activities in the sunshine of Haikou's vibrant climate.
In September, Haikou experiences a transitional shift in precipitation, with 71 mm (2.8 in) of rainfall over approximately 9 days. This marks a noticeable decrease from the peak wet months of June and July, which often bring torrential downpours. While September's rainfall is less intense, it still contributes to the overall yearly total, maintaining the humid atmosphere typical of the region. As the month progresses, the frequency of rain diminishes, signaling the gradual transition into drier autumn months. This trend of fluctuating precipitation underscores Haikou’s unique climatological patterns, blending both wet and dry elements throughout the year.
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.
As September rolls into Haikou, the UV Index remains notably high at 10, signaling a very high exposure category. This trend reflects the intense sunlight that persists in the region, even as summer transitions to autumn. Residents and visitors should take precautions, as the burn time is reduced to just 15 minutes—a reminder of the fierce sun, comparable to the preceding months of summer when the index peaked at 12. While the UV levels drop slightly in October to 8, September’s UV conditions underscore the need for effective sun protection. For a detailed analysis of UV trends throughout the year, visit Haikou UV Index.
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September in Haikou, China, marks a notable transition in sunshine hours, with the city basking in 266 hours of radiant light. This month experiences a slight dip from the sun-drenched days of August, which saw an impressive 315 hours of sunshine. However, September still remains abundant with sunshine, well above the earlier months of the year. As the year progresses, a clear trend emerges: from January's 159 hours to the peak of summer in July, sunshine consistently increases, culminating in the vibrant summer months. Each seasonal shift brings its own charm, but September continues to offer a warm embrace of daylight, making it a delightful time for residents and visitors alike to enjoy the outdoors in Haikou.
In September, Haikou, China, experiences a notable increase in the likelihood of sunny weather, with the chance of sun soaring to 61%. This marks a significant contrast to the summer months, particularly June and July, where sunny days are less frequent at only 16% and 20%, respectively. Following the relatively cloudy days of spring, September heralds the transition into a drier season, thus providing residents and visitors alike with an opportunity to bask in the sunshine. As the year progresses towards October, the chance of sunshine dips slightly to 39%, making September an ideal time to enjoy the outdoors 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.
As the summer heat begins to wane in September, the wind in Haikou, China, shows a gentle but noticeable shift, maintaining a consistent average speed of 1.7 m/s (4 mph). This marks a continuation of the lighter breezes experienced in the preceding months of June and August, where the winds dipped slightly to 1.6 m/s and 1.7 m/s respectively. However, September doesn't fall short; it hints at the approach of invigorating autumn winds, foreshadowed by the seasonal uptick to 2.2 m/s in July and an increase to 2.4 m/s in October. As such, September serves as a delicate bridge between summer's languid breezes and the refreshing gusts that autumn brings, creating an ideal atmosphere for leisurely outdoor activities while enjoying the tranquil yet mild winds.
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 present distinct weather contrasts. In September, temperatures range from a mild 17°C (63°F) at night to a scorching 38°C (101°F) during the day, accompanied by relatively high humidity at 72%. It also sees about 71 mm (2.8 in) of precipitation over 9 days. In contrast, January brings much cooler temperatures, with a minimum of -5°C (24°F) and a maximum of 24°C (75°F), averaging only 8°C (46°F). Despite similar precipitation levels of 70 mm (2.7 in) spread over the same number of days, January's humidity is slightly lower at 65%. For a deeper look into the January climate, you can visit Haikou weather in January.
September and February present quite contrasting weather patterns. In September, temperatures soar with a minimum of 17°C (63°F) and an average of 27°C (80°F), peaking at a hot 38°C (101°F). The month sees moderate precipitation of 71 mm (2.8 in) over about 9 days, along with a humidity level of 72%, creating a warm and muggy atmosphere. In stark contrast, February experiences much cooler temperatures with a minimum of -3°C (26°F) and an average of just 9°C (48°F), while the maximum reaches 26°C (79°F). Though it has slightly higher precipitation at 83 mm (3.3 in) over 12 days, the humidity remains similar at 71%. For a more detailed look at February weather, visit Haikou weather in February.
In September, the weather is generally warm, with temperatures ranging from a minimum of 17°C (63°F) to a maximum of 38°C (101°F), and an average temperature of 27°C (80°F). The humidity is relatively high at 72%, and there's moderate rainfall, with 71 mm (2.8 in) spread over 9 days. In contrast, March presents a cooler climate, with temperatures varying from a low of 3°C (38°F) to a high of 30°C (86°F) and an average of 14°C (58°F). This month is significantly wetter, experiencing about 205 mm (8.1 in) of precipitation over 16 days, coupled with slightly higher humidity at 81%. For more detailed insights, you can visit Haikou weather in March.
September and April present contrasting weather conditions. In September, temperatures range from a minimum of 17°C (63°F) to a scorching maximum of 38°C (101°F), with an average of 27°C (80°F). The month experiences moderate precipitation, with about 71 mm (2.8 in) spread over 9 days and a humidity level of 72%. In stark contrast, April sees much cooler temperatures, with a minimum of 5°C (41°F) and an average of 18°C (65°F), peaking at 33°C (91°F). Rainfall is significantly heavier in April, totaling 179 mm (7.0 in) over 14 days, accompanied by higher humidity at 86%. For more detailed information, check Haikou weather in April.
In comparing the weather of September and May, it’s clear that both months present unique characteristics. September typically enjoys warmer temperatures, ranging from a minimum of 17°C (63°F) to a maximum of 38°C (101°F), with an average of 27°C (80°F). The month experiences relatively moderate precipitation of 71 mm (2.8 in) over 9 days, accompanied by a humidity level of 72%.
In contrast, May is cooler with temperatures varying between a minimum of 11°C (52°F) and a maximum of 36°C (97°F), averaging at 23°C (74°F). However, it sees significantly heavier rainfall, totaling 244 mm (9.6 in) over 16 days, and a higher humidity level of 87%.
For a deeper look at the climatic conditions, you can refer to Haikou weather in May.
September and June exhibit notable differences in weather patterns. In September, temperatures range from a minimum of 17°C (63°F) to a maximum of 38°C (101°F), with an average of 27°C (80°F). The month experiences 71 mm (2.8 in) of precipitation over about 9 days, and humidity levels average around 72%. Conversely, June is slightly cooler, with temperatures varying from 17°C (63°F) to 36°C (98°F), averaging 26°C (79°F). However, it is far rainier, receiving 407 mm (16.0 in) of precipitation across 20 days, and humidity peaks at a higher 87%. For more details, you can check Haikou weather in June.
In September, temperatures are slightly cooler than in July, with a minimum of 17°C (63°F) and an average of 27°C (80°F), contrasted with July's minimum of 21°C (70°F) and average of 29°C (85°F). While both months experience high maximum temperatures, July peaks at 39°C (103°F), just above September's maximum of 38°C (101°F). Additionally, September has significantly less precipitation, recording 71 mm (2.8 in) over 9 days, compared to July’s hefty 300 mm (11.8 in) over 16 days. The humidity also differs notably, with September at 72% and July relatively higher at 91%. For more details on July weather, you can check Haikou weather in July.
When comparing the weather in September to that of August, there are several notable differences. September experiences slightly cooler temperatures, with a minimum of 17°C (63°F) and an average of 27°C (80°F), compared to August's minimum of 22°C (71°F) and average of 30°C (86°F). Additionally, September has a maximum temperature of 38°C (101°F), which is lower than August's peak of 41°C (105°F). Precipitation is also reduced in September, with 71 mm (2.8 in) over 9 days, whereas August sees significantly higher precipitation at 119 mm (4.7 in) over 13 days. Humidity levels are higher in August at 87%, compared to September's 72%. For more insights into August's weather, visit Haikou weather in August.
In September, the weather is typically warmer with average temperatures ranging from a minimum of 17°C (63°F) to a maximum of 38°C (101°F), making it feel quite hot, especially in the afternoons. The month also experiences higher precipitation, with about 71 mm (2.8 in) over 9 days, contributing to a humidity level of 72%. In contrast, October brings cooler temperatures, averaging between 11°C (51°F) and 36°C (97°F), with an overall average of 21°C (70°F). The month is drier, with only 40 mm (1.6 in) of rain across 6 days and a slight increase in humidity to 74%. For a detailed look at what to expect, check out Haikou weather in October.
September and November present a striking contrast in weather. September enjoys warmer temperatures, with averages reaching 27°C (80°F) and highs soaring to 38°C (101°F), while November experiences a cooler climate, with average temperatures dropping to 15°C (59°F) and maximums peaking at 29°C (85°F). Both months see similar levels of precipitation, around 70 mm (2.8 in), with September slightly less rainy over 9 days compared to November’s 10 days. Additionally, November's humidity is a touch higher at 80%, compared to September’s 72%. For a closer look at the weather specifics, check out Haikou weather in November.
September and December present starkly contrasting weather conditions. September typically enjoys warmer temperatures, with averages around 27°C (80°F) and highs reaching up to 38°C (101°F), accompanied by a moderate level of humidity at 72%. The month also sees about 71 mm (2.8 in) of precipitation over approximately 9 days. In contrast, December brings much cooler temperatures, where the average plummets to 9°C (49°F), with minimums dipping as low as -2°C (28°F) and maximums reaching a mild 23°C (74°F). Precipitation in December is slightly less, totaling 57 mm (2.2 in) over about 8 days, while humidity rises to 78%. For more detailed information, check Haikou weather in December.
As September arrives in Haikou, the weather takes on distinct characteristics that set it apart from other months. This transitional time offers a welcome relief from the peak summer heat, with average temperatures around 27°C (80°F), though the maximum can still reach a sizzling 38°C (101°F). Visitors can expect a touch of humidity, averaging 72%, and occasional rainfall, with 71 mm (2.8 in) of precipitation spread over 9 days. The blend of warm temperatures and sporadic showers creates a unique atmosphere, perfect for enjoying both sunlit days and the refreshing breaks brought by the rain. For those looking to explore the climate further, more detailed information can be found at Haikou Climate.