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Hourly Forecast
Daylight Hours
06:31
Sunrise
18:30
Sunset
Moon
Waxing Gibbous
15:05
Moonrise
02:13
Moonset
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View stargazing scoreWeather in Haikou today, September 21, 2026
Rain features in Haikou on September 21, 2026, so keep waterproofs handy through the day. The damp theme is strongest where shower chances rise. Morning skies stay relatively clear, holding cloud close to 10% near 10:00. The early part of the day favours being outside.
The day peaks near 31°C and cools toward 24°C. The air stays humid, with relative humidity between 68% and 98% and the peak around 05:00. Airflow remains manageable, reaching about 4.4 km/h around 17:00.
Afternoon showers stay in play, peaking near 24% around 12:00. Skies remain cluttered, with cover about 28% by 23:00. Horizontal visibility holds close to 16.1 km. The sun rises at 06:31 and sets at 18:30, for a total of 11 hours 59 minutes of sunlight today.
The practical takeaway for Haikou on September 21, 2026 is simple: plan for rain, keep layers handy, and work around a high of about 31°C.
Frequently asked questions about weather in Haikou
How warm does it get in Haikou?
The warmest month in Haikou is June, with average high temperatures of 31°C. The average temperature during this period is around 29°C.
How cold does it get in Haikou?
The coldest month in Haikou is January, with average low temperatures of 18°C. The average temperature during this period is around 19°C.
What is the wettest time of year in Haikou?
The wettest month in Haikou is August, with an average of 263mm of precipitation.
What is the driest time of year in Haikou?
The driest month in Haikou is December, with an average of 21mm of precipitation.
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