Weather in Hainan for September 2025
Rainstorm Warning - See hour by hour.
Until now, September 2025 in Hainan has been nearly identical to the historical average, with a temperature of 30.3 °C (showing only a slight deviation of -0.2 °C).
Expect cooler weather in the next days in Hainan with the forecast suggesting a temperature of 28.3 °C, lower than the historical average.
In general, the average temperature in Hainan at the beginning of September is 31.1 °C. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 28.1 °C by the end of September.
Hainan experiences heavy rainfall in September, with over 20 rainy days and an average total precipitation 422.5 mm.
Is September a good time to visit Hainan? check out the best time to travel to Hainan page.
New! Chat with our AI weatherman - it’s amazing and free.
Official Weather Alert ⚠️
Temperatures
Rain 🌧️
More
Hainan Weather September
What’s the Weather Like in Hainan This September?
Temperatures trend during September in Hainan
September weather in Hainan day by day
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 Sept. |  Moderate or heavy rain with thunder | 32° /23° | 6.5 mm | 7 | |
| 2 Sept. | Moderate or heavy rain with thunder | 32° /23° | 12.1 mm | 7 | |
| 3 Sept. |  Light rain shower | 32° /23° | 5.5 mm | 7 | |
| 4 Sept. | Patchy rain possible | 32° /24° | 3.2 mm | 7 | |
| 5 Sept. | Light rain shower | 32° /24° | 11.6 mm | 7 | |
| 6 Sept. |  Patchy light rain with thunder | 30° /23° | 24.6 mm | 7 | |
| 7 Sept. |  Moderate or heavy rain shower | 28° /23° | 86.5 mm | 6 | |
| 8 Sept. | Patchy light rain with thunder | 30° /23° | 5.8 mm | 7 | |
| 9 Sept. | Moderate or heavy rain shower | 31° /23° | 22.1 mm | 7 | |
| 10 Sept. | Light rain shower | 27° /23° | 10.9 mm | 6 | |
| 11 Sept. |  Patchy light drizzle | 29° /23° | 3.4 mm | 7 | |
| 12 Sept. | Light rain shower | 30° /23° | 2 mm | 7 | |
| 13 Sept. | Patchy light rain with thunder | 31° /22° | 11 mm | 7 | |
| 14 Sept. | Patchy rain possible | 30° /23° | 7.5 mm | 7 | |
| 15 Sept. | Light rain shower | 31° /23° | 6.4 mm | 7 | |
| 16 Sept. | Patchy light rain with thunder | 31° /23° | 2.4 mm | 7 | |
| 17 Sept. |  Moderate rain | 29° /22° | 10.9 mm | 2.8 | |
| 18 Sept. | Patchy rain possible | 29° /23° | 3.9 mm | 2.8 | |
| 19 Sept. | Moderate rain | 30° /23° | 9 mm | 2.8 | |
| 20 Sept. | Moderate rain | 31° /22° | 6 mm | 3.2 | |
| 21 Sept. | Patchy rain possible | 29° /23° | 1.3 mm | 6 | |
| 22 Sept. | Moderate rain | 28° /23° | 15.5 mm | 5 | |
| 23 Sept. |  Heavy rain | 26° /23° | 42.5 mm | 5 | |
| 24 Sept. | Patchy rain possible | 28° /22° | 1.7 mm | 5 | |
| 25 Sept. | Patchy rain possible | 26° /21° | 0.1 mm | 5 | |
| 26 Sept. | Patchy rain possible | 28° /20° | 0.5 mm | 5 | |
| 27 Sept. | Patchy rain possible | 27° /21° | 0.5 mm | 5 | |
| 28 Sept. | Patchy rain possible | 28° /20° | 0.2 mm | 5 | |
| 29 Sept. |  Partly cloudy | 29° /21° | 0.1 mm | 6 | |
| 30 Sept. | Patchy light drizzle | 31° /23° | 5.1 mm | 7 | |
| Next | |||||
Hainan weather in September vs August vs October
| August | September | October | |
|---|---|---|---|
| Weather | Patchy rain possible | Patchy rain possible | Patchy rain possible |
| Temperatures | 33°/24° | 30°/23° | 27°/21° |
| Rainfall | 147 mm | 423 mm | 357 mm |
| Wind | 11.7 km/h | 15.1 km/h | 18.2 km/h |
| Humidity | 76% | 87% | 84% |
| Rainy days | 21 days | 26 days | 21 days |
| Dry days | 10 days | 4 days | 10 days |
Planning a trip to Hainan? Discover the best time to visit
Hainan in September - FAQ
What to pack to Hainan in September?
As you prepare for your trip to Hainan in September, it's important to consider the typical weather patterns for the time of year. Below is a carefully tailored packing list to ensure that your time in Hainan, during September, is comfortable and enjoyable, regardless of the weather conditions.
- Clothing
- Lightweight Clothing: T-shirts, blouses, shorts, skirts
- Rain Gear: Lightweight, waterproof clothing
- Footwear
- Waterproof Shoes
- Sandals/Flip-flops: Comfortable for warm climates
- Accessories
- Sunglasses: For sun protection
- Sun Hats: Wide-brimmed hats for sun protection in warm weather
- Umbrellas/Raincoats: For rainy days
- Personal Items
- Sunscreen: High SPF for sunny destinations
- Lip Balm with SPF: To protect against chapped lips
- Insect Repellent: For destinations with mosquitos or other insects
September rainfall patterns in Hainan
UV exposure in Hainan during September
Quick links
Where is Hainan?Get accurate weather forecasts for Hainan, located at latitude 19.2 and longitude 109.7. Stay updated with localized weather information tailored for Hainan.