Hainan in Summer
In summer (June, July and August), Hainan sees average daytime highs around 26°C and overnight lows near 16°C, with 405 mm of rain over about 42 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 26°C. The sky is clear or mostly clear about 25% of the time across summer, and the air most often feels humid.
Summer is Hainan's best season of the year to visit on our travel score. For the whole year in context, see Hainan's year-round climate.
- Avg daytime high
- 26°C
- warmest season of the year
- Avg overnight low
- 16°C
- Rainfall
- 405 mm
- 42 wet days
- Avg wind
- 10 km/h
- Travel score
- 6.0
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Hainan in Summer
Across summer, daytime highs hold fairly steady around 26°C.
A typical summer day in Hainan reaches about 26°C and drops to 16°C overnight. The warmest of the three months is July, the coolest June.
How summer really feels in Hainan
Once humidity and wind are folded in, summer brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Hainan weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | -15° / -26° | 4 | 1.1 | 1.6 | 8.7 | 0.0 |
| Feb | -9° / -22° | 6 | 1.6 | 1.9 | 10 | 0.0 |
| Mar | 1° / -11° | 16 | 3.6 | 3.3 | 11.6 | 0.1 |
| Apr | 12° / 0° | 33 | 5.6 | 1.2 | 13.3 | 3.2 |
| May | 20° / 8° | 62 | 9.9 | 0.1 | 14.8 | 6.2 |
| Jun | 25° / 15° | 101 | 13.3 | 0 | 15.6 | 6.1 |
| Jul | 27° / 18° | 162 | 14.7 | 0 | 15.3 | 5.8 |
| Aug | 25° / 16° | 143 | 13.6 | 0 | 14 | 6.2 |
| Sep | 20° / 8° | 73 | 9.1 | 0 | 12.4 | 6.4 |
| Oct | 10° / -0° | 37 | 6.9 | 0.9 | 10.6 | 2.7 |
| Nov | -3° / -12° | 14 | 3.2 | 2.9 | 9.1 | 0.0 |
| Dec | -13° / -23° | 8 | 2.6 | 3.4 | 8.3 | 0.0 |
Cloud cover in Summer
The sky is clear or mostly clear about 25% of the time across summer.
Chance of precipitation in Summer
Hainan gets around 405 mm of rain over 42 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 10 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 15 h 24 min in early June to 13 h 18 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.2 kWh/m².
Hazard calendar for Hainan
In summer, Hainan overlaps its rainy season season. The full year is below, with each hazard's peak months called out.
Hainan's rainy season runs June–September, when most of the year's rain falls.
Is summer a good time to visit Hainan?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Hainan for sightseeing.
What to pack for Hainan in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Hainan sees daytime highs around 26°C and nights near 16°C. Pack rain gear. Worth having: light clothes and sun protection. About 42 days see rain.
UV index in Hainan in Summer
Clear-sky midday UV across summer averages around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Hainan peaks around August 17 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 19 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 6 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 1 | 3 | 4 | 5 | 6 | 5 | 7 | 5 | 2 | 1 | 1 |
| Level | Low | Low | Moderate | Moderate | High | High | Moderate | Very high | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 1 | Low |
| Mar | 3 | Moderate |
| Apr | 4 | Moderate |
| May | 5 | High |
| Jun | 6 | High |
| Jul | 5 | Moderate |
| Aug | 7 | Very high |
| Sep | 5 | Moderate |
| Oct | 2 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Air quality in Hainan in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Hainan is worst in March — around 37 µg/m³ PM2.5 (poor), about 2.3× the cleanest month (August, 16 µg/m³).
Seasonal pattern from CAMS reanalysis, scaled to Hainan's WHO annual average of 25 µg/m³.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 31 | 31 | 37 | 30 | 21 | 19 | 20 | 16 | 17 | 22 | 28 | 27 |
| Level | Moderate | Moderate | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 31 | Moderate |
| Feb | 31 | Moderate |
| Mar | 37 | Poor |
| Apr | 30 | Moderate |
| May | 21 | Moderate |
| Jun | 19 | Moderate |
| Jul | 20 | Moderate |
| Aug | 16 | Moderate |
| Sep | 17 | Moderate |
| Oct | 22 | Moderate |
| Nov | 28 | Moderate |
| Dec | 27 | Moderate |
Where is Hainan?
Hainan sits at 47.2°N, 127.0°E, 0 m above sea level, in China. The nearest listed city is Harbin, 167 km away.
Topography around Hainan
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Hainan.
Within 3 km, the terrain around Hainan has only modest variations in elevation — a maximum elevation change of 73 m around an average of 214 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 91 m; within 80 km, significant variations in elevation — a maximum elevation change of 538 m.
The land around Hainan is covered by cropland (87%) within 3 km, cropland (89%) within 16 km, and cropland (82%) within 80 km.
China travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type A / I
- 220 V · 50 Hz
- Prices
- ≈ 47% of US
- price level, 2025
- GDP per capita
- $13,862
- 2025
- Happiness
- 6.1 / 10
- World Happiness, 2025
- Homicide rate
- 0.5
- per 100k, 2020
- Road deaths
- 17.4
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 464
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Hainan (47.2322°, 126.9809°, elevation 0 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.