Jeju weather in August
Temperature, sea and sunshine in August: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in August
Fair
Best time to visit: April – June, September – October
What is the weather like in Jeju in August?
In August, Jeju is hot: daytime highs average 29 °C, and even at night it stays warm at around 26 °C. The sea averages 27.0 °C – lovely and warm for swimming. Expect around 6 hours of sunshine a day. It rains often – on about 17 days, adding up to 214 mm. On about 8 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, August is a so-so month for a holiday in Jeju.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 61 | 52 | 67 |
| Day | 27° | 29° | 25° |
| Night | 24° | 26° | 22° |
| Sea | 24° | 27° | 25° |
| Sun | 6 h | 6 h | 5 h |
| Rain days | 17 | 17 | 14 |
More details for August
- Daylight
- 13 h 26 min05:56 – 19:22
- UV index
- 10 · very highclear sky, noon (estimate)All months
- Muggy days
- 31 daysdew point 18 °C or moreAll months
- Wind
- 16 km/haverage daily peakAll months
- Cloud cover
- 63 %on averageAll months
- Hot days
- 8 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snow
- Time zone
- UTC+9Asia/Seoul
How the score comes together
- Temperatureweight 50 %80 %
- Sunshineweight 20 %55 %
- Few rainy daysweight 30 %4 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in August
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Insect repellent
- Rain jacket or umbrella
Jeju in August: quick answers
Is Jeju hot in August?
Yes. In August, Jeju is hot: daytime highs average 29 °C and nights stay around 26 °C. On about 8 days the thermometer climbs to 30 °C or more.
Can you swim in Jeju in August?
Yes. In August the sea averages 27.0 °C – lovely and warm for swimming.
Does it rain much in Jeju in August?
It rains often – on about 17 days, adding up to 214 mm.
Jeju month by month
The whole year in JejuAll destinations: South KoreaWhere to go in AugustSea temperature in August
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences