Last updated: August 21, 2025
In September, Haikou, China experiences a warm climate, characterized by a maximum temperature reaching 33°C (91°F) and an average of 28°C (83°F). The temperature typically dips to a minimum of 25°C (77°F), providing a tropical ambiance. However, this month also sees significant precipitation, with 159 mm (6.3 in) spread across approximately 18 rainy days. The weather is marked by a notably high humidity level of 82%, making it vital for visitors to stay hydrated and prepared for the occasional rain shower while enjoying the lush landscapes of this beautiful coastal city.
In September, Haikou, China experiences warm and inviting temperatures that signal the transition from the summer heat. With minimums rising to 25°C (77°F) and averages settling around 28°C (83°F), the city remains comfortably warm, perfect for outdoor activities. The maximum temperatures reach up to 33°C (91°F), resembling the summer months while hinting at the cooler days ahead in October. This slight dip from the peak summer highs suggests a gradual shift, making September an excellent time for visitors to enjoy the lingering warmth before the temperatures begin to cool significantly in the ensuing months. The pleasant climate, coupled with a vibrant atmosphere, makes it an ideal time for exploring Haikou's scenic beauty and rich culture.
In September, Haikou experiences a significant amount of rainfall, with 159 mm (6.3 in) recorded over 18 days, making it one of the wetter months of the year. This level of precipitation follows August’s peak of 275 mm (10.8 in), indicating the tail end of the monsoon season. Remarkably, while September maintains a high rainfall volume, the number of precipitation days remains consistent at 18—suggesting that rainfalls may be heavier but less frequent compared to the previous month. The transition into autumn is evident as locals brace for slightly drier days ahead in October, where rainfall increases again to 215 mm (8.5 in) as the region begins to prepare for seasonal shifts. Overall, September serves as a bridge in Haikou's climatic rhythm, linking the intense rains of summer with the forthcoming variations of fall.
In September, Haikou experiences a notable dip in humidity at 82%, a slight decrease from the sweltering heights of summer. The city's humidity reaches its peak in July and August, at a staggering 87% and 86% respectively, creating a tropical atmosphere that can feel quite oppressive. As the seasons shift towards autumn, September brings a refreshing transition, with humidity levels softening to make outdoor activities more enjoyable. This pattern continues into the fall months, with October and November maintaining relatively comfortable humidity levels around 81% and 80%. Overall, while Haikou's climate is consistently humid throughout the year, September serves as a transitional month, offering a brief respite from the summer’s intense moisture.
September in Haikou, China, sees a persistently high UV Index of 13, placing it in the extreme exposure category with a burn time of just 10 minutes. This trend of elevated UV levels has been consistent throughout the summer months, reflecting a peak in solar intensity that started in May and continues into September. With the UV Index remaining at this elevated level, residents and visitors alike should take careful precautions to protect their skin from harmful rays. As autumn approaches, the UV Index is expected to gradually decrease, but September remains a critical month for sun safety. For more detailed information, visit Haikou UV Index.
UV Risk Categories
September in Haikou, China, brings a delightful balance of warmth and sunshine, with an impressive 294 hours of bright daylight. This month stands out as a continuation of the summer's radiant streak, nestled between the peak sunshine months of July and August, which boast 318 and 286 hours respectively. Following the sun-drenched days of May and June, where residents basked in 314 and 304 hours, September maintains a strong luminosity, while smoothly transitioning towards the milder months of October and November. This subtle decline, as daylight hours retreat to 278 and 256, sets the stage for a cozy and inviting autumn, making September a notable highlight in Haikou’s sun-filled calendar.
In Haikou, China, September presents a moderate chance of sunny weather with a 42% likelihood of sunshine. This marks a slight increase from the gloomy summer months of June (17%), July (33%), and August (21%), where clouds often overshadowed the sun. As the region transitions into the fall, September's weather patterns reflect a gradual return to brighter skies, even if they remain below the year’s average peak in late winter and early spring. Notably, the upcoming months showcase a rebound, especially in November, which boasts a 54% chance of sun, hinting at the welcoming warmth on the horizon after the heat of summer.
In Haikou, China, the month of September brings a delightful balance of 12 hours of daylight, continuing the trend of gradually waning hours as autumn approaches. Following the summer months, where daylight peaked at 13 hours in June, July, and August, September signals a subtle shift towards shorter days. This transition reflects a harmonious rhythm in the region, as daylight begins to recede after a vibrant summer, setting the stage for cooler months ahead. As the year progresses, daylight in Haikou will progressively decrease, dipping down to 11 hours by October, reminding us of the cyclical beauty in nature's patterns.
As September rolls into Haikou, the gentle caress of the breeze becomes even more subtle, with average wind speeds dipping to 3.4 m/s (8 mph)—the lowest point of the year. This transition follows a summer filled with relatively stable wind patterns, where gusts hovered around the 4 m/s mark. Despite the decrease in wind speed this month, the climate remains pleasant, setting the stage for the brisker autumn winds that will soon follow, with October promising a revitalizing upturn at 6.8 m/s (15 mph). Overall, September offers a tranquil and mild atmosphere, inviting residents and visitors alike to savor the calm before the energizing shift that awaits in the fall.
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 offer contrasting weather experiences. In September, temperatures are significantly warmer, with a minimum of 25°C (77°F) and an average of 28°C (83°F), reaching a high of 33°C (91°F). This month also sees considerable rainfall, with 159 mm (6.3 in) spread over 18 days, combined with high humidity levels at 82%. In stark contrast, January brings a cooler climate with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 25°C (77°F), averaging 19°C (67°F). The precipitation is markedly lower at 23 mm (0.9 in) over just 6 days, and humidity decreases to 74%. For more details on January's weather, you can visit Haikou weather in January.
September and February present contrasting weather patterns. In September, temperatures soar with a minimum of 25°C (77°F) and an average around 28°C (83°F), peaking at 33°C (91°F). This month also experiences significant rainfall, totaling 159 mm (6.3 in) over 18 days, paired with high humidity at 82%. In contrast, February is much cooler, with temperatures ranging from a minimum of 10°C (51°F) to an average of 20°C (68°F) and a maximum of 29°C (84°F). February sees much less precipitation, only 39 mm (1.5 in) over 6 days, and a lower humidity level of 75%. For more details on February's weather, visit Haikou weather in February.
In September, the weather tends to be much hotter and more humid compared to March. With average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 33°C (91°F), September feels quite warm, especially with an 82% humidity level. Additionally, it experiences significant rainfall, with 159 mm (6.3 in) spread over 18 days. In contrast, March brings more moderate temperatures that range from a minimum of 16°C (61°F) to a maximum of 32°C (89°F), with a more pleasant average of 23°C (74°F). Precipitation is significantly lower in March, totaling only 30 mm (1.2 in) over 8 days, and the humidity is slightly lower at 78%. For more insights on March weather, check out Haikou weather in March.
When comparing the weather in September and April, September is notably warmer, with average temperatures reaching around 28°C (83°F) compared to April's milder average of 25°C (77°F). Both months experience a maximum temperature of 33°C (91°F in September and 92°F in April), but September sees significantly more rainfall, with 159 mm (6.3 in) over 18 days, while April has only 87 mm (3.4 in) spread over 13 days. Humidity levels are similar, at 82% in September and 80% in April, making both months feel quite humid. For more detailed information about April's weather, you can check Haikou weather in April.
In September, the weather is typically warmer, with average temperatures around 28°C (83°F) and maximums reaching up to 33°C (91°F), compared to May, where the average is the same but maxes out at 34°C (94°F). However, September experiences higher precipitation levels, with 159 mm (6.3 in) spread over 18 days, while May has a more moderate rainfall of 90 mm (3.6 in) over 16 days. Humidity levels remain similar, with September at 82% and May at 81%. This makes September feel a bit more humid, even though the overall temperatures are closely matched. For more details on May weather, you can visit Haikou weather in May.
When comparing the weather in September and June, both months showcase warm temperatures, but September tends to be slightly cooler overall. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 33°C (91°F), with an average temperature of 28°C (83°F). In contrast, June has slightly higher temperatures, averaging 29°C (85°F) and reaching up to 35°C (95°F). Despite the warmer average in June, it experiences a bit less rainfall than September, with 134 mm (5.3 in) of precipitation compared to September's 159 mm (6.3 in), although June has a similar number of rainy days. Humidity levels remain comparable, with September at 82% and June at 81%. For a more detailed look at June’s weather, you can explore Haikou weather in June.
In comparing the weather of September and July, both months exhibit warm temperatures and notable humidity. September experiences a slightly lower average temperature, with a minimum of 25°C (77°F) and a maximum of 33°C (91°F), while July boasts a higher maximum temperature of 36°C (97°F) and an average of 29°C (85°F). Precipitation is quite similar, with September receiving 159 mm (6.3 in) of rain and July slightly higher at 169 mm (6.6 in), both spanning 18 rainy days. Humidity is also elevated in both months, with September at 82% and July topping at 87%. For a more detailed look at July's climate, you can check out Haikou weather in July.
In comparing the weather of September and August, we see quite similar temperatures, with September showcasing a minimum of 25°C (77°F) and an average of 28°C (83°F), compared to August's slightly warmer minimum of 26°C (78°F) and average of 29°C (84°F). Both months reach a maximum of 33°C (91°F) in September and 33°C (92°F) in August, highlighting consistent heat. However, September experiences noticeably less rainfall, with 159 mm (6.3 in) over 18 days, whereas August sees significantly higher precipitation at 275 mm (10.8 in) across 21 days. Additionally, humidity is slightly lower in September at 82%, compared to 86% in August. For more detailed information on August weather, you can refer to Haikou weather in August.
September tends to be warmer than October, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 33°C (91°F). In contrast, October experiences slightly cooler conditions, with temperatures averaging between 21°C (70°F) and 31°C (88°F). Both months see significant rainfall, but October is wetter, accumulating 215 mm (8.5 in) compared to September's 159 mm (6.3 in), although both months experience precipitation on approximately 18 days. Humidity levels remain high, with September having an average of 82% and October slightly lower at 81%. For more detailed insights on October's weather, check out Haikou weather in October.
September and November present distinct weather patterns. In September, temperatures are notably higher, with minimums around 25°C (77°F) and maximums reaching up to 33°C (91°F), coupled with significant rainfall of 159 mm (6.3 in) over 18 days, resulting in a humid environment at 82% humidity. In contrast, November experiences milder temperatures, with a minimum of 17°C (63°F) and a maximum of 28°C (83°F), along with much lower precipitation of just 43 mm (1.7 in) over 9 days, contributing to a slightly reduced humidity of 80%. For more detailed information, you can check Haikou weather in November.
The weather in September is notably warmer and more humid than in December. September boasts a minimum temperature of 25°C (77°F) and averages around 28°C (83°F), with highs reaching up to 33°C (91°F). This month also experiences significant rainfall, with 159 mm (6.3 in) of precipitation over 18 days and humidity levels at 82%. In contrast, December offers a much cooler climate, with temperatures ranging from a minimum of 13°C (56°F) to a maximum of 27°C (80°F), and an average of 20°C (69°F). Additionally, December sees a dramatic decrease in precipitation, totaling just 28 mm (1.1 in) over 8 days, along with a slight drop in humidity to 79%. For more details, you can check Haikou weather in December.
September in Haikou showcases a transitioning climate, where the humidity lingers at a high 82%, making the warmth feel even more intense. Compared to other months, the temperature starts to dip slightly, offering a balance between hot days and cooler evenings. However, this month also brings significant rainfall, with 18 days of precipitation resulting in a total of 159 mm, making it one of the wetter periods of the year. This shift in weather conditions creates a dynamic atmosphere, perfect for experiencing Haikou's lush landscapes. For more detailed insights into the climate, visit Haikou Climate.