Sanya south coast: Yalong Bay, Dadonghai
Best months: November to May. Rainiest: July to October. Highs range from 76°F (24°C) to 87°F (31°C), sea 75–86°F (24–30°C).
Best Time to Visit Hainan
The best time to visit Hainan: in Sanya, November to May; in Haikou, March to April, November. The wettest stretch in Haikou is June, August, October. It is hottest in Haikou in June, with highs of 90°F (32°C). It is coolest in Haikou in January, with highs of 69°F (21°C). Humidity ranges from 73–85% through the year.
Climate normals were checked on September 29, 2026, over a year ago. An update is due.
Climate normals checked September 29, 2026 · Source: Open-Meteo (ERA5) · How we calculate
Hainan weather by month
Colour shows the month rating for the best region. See the table below for month-by-month details.
- Jan76°FJanuary: Good
- Feb77°FFebruary: Good
- Mar81°FMarch: Good
- Apr84°FApril: Excellent
- May87°FMay: Good
- Jun87°FJune: Mixed
- Jul89°FJuly: Mixed
- Aug87°FAugust: Mixed
- Sep86°FSeptember: Mixed
- Oct82°FOctober: Mixed
- Nov82°FNovember: Excellent
- Dec77°FDecember: Excellent
Excellent Good Mixed Off-season
Hainan air and sea temperature by month
- Sanya: air
- Sanya: sea
- Haikou: air
- Haikou: sea
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sanya: air | 76 | 77 | 81 | 84 | 87 | 87 | 87 | 87 | 86 | 84 | 82 | 77 |
| Sanya: sea | 76 | 75 | 76 | 81 | 84 | 87 | 85 | 84 | 85 | 84 | 81 | 78 |
| Haikou: air | 69 | 72 | 79 | 84 | 88 | 90 | 89 | 88 | 86 | 82 | 78 | 71 |
| Haikou: sea | 68 | 69 | 72 | 79 | 83 | 87 | 88 | 88 | 87 | 83 | 77 | 72 |
Hainan weather table, month by month
Long-term averages for each region. Tap a region to open its table.
Sanya · south coast: Yalong Bay, Dadonghai
| Month | Day high | Night low | Sea | Rainy days | Rainfall | Humidity | Sun, h/day |
|---|---|---|---|---|---|---|---|
| January | 76°F (24°C) | 66°F (19°C) | 76°F (24°C) | 4 | 0.9 in (24 mm) | 77% | 9.1 |
| February | 77°F (25°C) | 67°F (19°C) | 75°F (24°C) | 3 | 0.6 in (15 mm) | 78% | 9.8 |
| March | 81°F (27°C) | 72°F (22°C) | 76°F (25°C) | 6 | 0.7 in (18 mm) | 82% | 10.7 |
| April | 84°F (29°C) | 76°F (24°C) | 81°F (27°C) | 10 | 1.4 in (35 mm) | 82% | 11.3 |
| May | 87°F (31°C) | 80°F (26°C) | 84°F (29°C) | 18 | 4.4 in (113 mm) | 84% | 11.0 |
| June | 87°F (31°C) | 81°F (27°C) | 87°F (30°C) | 22 | 7.4 in (188 mm) | 84% | 10.9 |
| July | 87°F (30°C) | 80°F (27°C) | 85°F (29°C) | 24 | 10.7 in (271 mm) | 84% | 10.1 |
| August | 87°F (30°C) | 80°F (26°C) | 84°F (29°C) | 23 | 8.2 in (209 mm) | 85% | 10.1 |
| September | 86°F (30°C) | 78°F (26°C) | 85°F (30°C) | 22 | 8.3 in (211 mm) | 85% | 9.4 |
| October | 84°F (29°C) | 76°F (24°C) | 84°F (29°C) | 17 | 9.2 in (233 mm) | 81% | 8.9 |
| November | 82°F (28°C) | 73°F (23°C) | 81°F (27°C) | 6 | 1.6 in (40 mm) | 78% | 10.2 |
| December | 77°F (25°C) | 67°F (20°C) | 78°F (26°C) | 3 | 0.9 in (23 mm) | 73% | 9.2 |
Haikou · north coast
| Month | Day high | Night low | Sea | Rainy days | Rainfall | Humidity | Sun, h/day |
|---|---|---|---|---|---|---|---|
| January | 69°F (21°C) | 63°F (17°C) | 68°F (20°C) | 10 | 2.0 in (51 mm) | 83% | 6.8 |
| February | 72°F (22°C) | 64°F (18°C) | 69°F (21°C) | 7 | 1.5 in (39 mm) | 84% | 7.4 |
| March | 79°F (26°C) | 69°F (21°C) | 72°F (22°C) | 8 | 1.6 in (40 mm) | 84% | 8.9 |
| April | 84°F (29°C) | 74°F (23°C) | 79°F (26°C) | 12 | 3.1 in (79 mm) | 82% | 10.1 |
| May | 88°F (31°C) | 78°F (26°C) | 83°F (29°C) | 18 | 6.0 in (152 mm) | 83% | 10.7 |
| June | 90°F (32°C) | 81°F (27°C) | 87°F (31°C) | 19 | 8.0 in (203 mm) | 82% | 11.1 |
| July | 89°F (32°C) | 80°F (27°C) | 88°F (31°C) | 19 | 8.0 in (202 mm) | 81% | 11.0 |
| August | 88°F (31°C) | 80°F (27°C) | 88°F (31°C) | 21 | 11.2 in (285 mm) | 84% | 9.8 |
| September | 86°F (30°C) | 79°F (26°C) | 87°F (30°C) | 19 | 7.8 in (197 mm) | 85% | 9.3 |
| October | 82°F (28°C) | 76°F (24°C) | 83°F (28°C) | 18 | 8.7 in (222 mm) | 81% | 8.5 |
| November | 78°F (26°C) | 72°F (22°C) | 77°F (25°C) | 11 | 2.8 in (72 mm) | 81% | 8.4 |
| December | 71°F (22°C) | 66°F (19°C) | 72°F (22°C) | 8 | 1.2 in (31 mm) | 78% | 6.6 |
Best time to visit Hainan for beaches, sightseeing and savings
| Goal | When to go |
|---|---|
| Beach holiday | Sanya: March to May, November to January Haikou: April, November |
| Sightseeing | Sanya: November to April Haikou: November to April |
| Peak season | April, November to December |
| Cheaper: shoulder season | January, March, May, October |
- Beach holiday — sea 75°F (24°C)+, highs 75–95°F (24–35°C), rain under 150 mm
- Sightseeing — highs 63–88°F (17–31°C), rain under 100 mm
- Peak season — the best weather rating of the year
- Cheaper: shoulder season — months next to peak season, weather still decent
Shoulder season is a weather-based estimate, not a price check: demand is lower in these months, so flights and hotels are usually cheaper than at peak. We do not compare prices here; check them for your dates.
- Compare with other destinations: where to go in April, where to go in November, where to go in December.
How to use it
- Read the calendar: green is in season, red is off-season.
- Open a region table for highs and lows, sea temperature, rainfall, rainy days, humidity and sunshine.
- Pick your goal in the “When to go” block: beach, sightseeing or shoulder season.
- Compare with other destinations in “Where to go” for your month.
When to visit each region of Hainan
Haikou north coast
Best months: March to April, November. Rainiest: June to August, October. Highs range from 69°F (21°C) to 90°F (32°C), sea 68–88°F (20–31°C).
Best time to visit Hainan: FAQ
When is the best time to visit Hainan?
The best time to visit Hainan: in Sanya, November to May; in Haikou, March to April, November. The wettest stretch in Haikou is June, August, October. It is hottest in Haikou in June, with highs of 90°F (32°C). It is coolest in Haikou in January, with highs of 69°F (21°C). Humidity ranges from 73–85% through the year.
What is Hainan's rainy season?
Months with more than 200 mm (7.9 in) of rain: in Sanya, July to October; in Haikou, June to August, October. The wettest month in Haikou is August, with about 11.2 in (285 mm).
Is Hainan hot all year?
Day highs in Sanya range from 76°F (24°C) to 87°F (31°C). The hottest month is June in Haikou, at 90°F (32°C).
Where the data comes from
- Air temperature, rainfall, humidity — ERA5 reanalysis (Copernicus / ECMWF) via Open-Meteo, averaged over 2015–2024. Each region uses one point: the resort or city in its caption.
- Sea temperature — Open-Meteo Marine, average sea surface temperature for 2023–2026 (the source has no longer record yet).
- Sunshine — sunshine duration from the same ERA5 reanalysis (Open-Meteo), average hours of sun per day for the month, 2015–2024.
- Rainy days — days with at least 1 mm (0.04 in) of rain. Reanalysis picks up light rain more often than weather stations, so treat this as an upper bound.
- Month rating — one rule for every destination, based on three factors: day highs (ideal 75–91°F / 24–33°C), monthly rainfall (ideal under 80 mm / 3.1 in) and, for beach regions, sea temperature (ideal 77°F / 25°C or warmer). All ideal means Excellent; one slightly weaker factor means Good. Mixed means heavy rain (150 mm / 5.9 in or more), highs above 97°F (36°C) or a sea below 70°F (21°C). Off-season means highs of 100°F (38°C) or more, cold below 54°F (12°C), over 350 mm (13.8 in) of rain, or several problems at once. A country's rating follows its best region, so check the regional table.
- Licence — weather data by Open-Meteo.com under CC BY 4.0; ERA5 reanalysis by the Copernicus Climate Change Service / ECMWF. The normals are precomputed and stored on this site, so the page sends no requests to the source.
Checked September 29, 2026. Climate normals are refreshed yearly and the notes every 90 days. These are long-term averages, not a forecast: any given year can differ.
