The most comfortable time to visit Jeju is from May to June, and again from late September to October. For sun, aim for mid July; for walking, go from mid March to early June.
When to go five ratings · thirty-six ten-day sections · click a cell to read it
For sun, go in mid July. It peaks in mid July, at 56. That is a short window, about ten days a year. Avoid mid October to early May for this: it falls to 0, mostly because it is too cool. The clearest skies come in April, when the sky is typically 61% covered at midday (often cloudy).
The being outside season here runs from May to June, with a second spell from late September to October. It peaks in late May, at 84. The weakest stretch is from mid December to early February, when it drops to 0, mostly because it is too cold.
For walking, go from mid March to early June, with a second spell from October to November. It peaks in late October, at 83. Avoid mid July to August for this: it falls to 0, mostly because it is too warm.
The year, measured
The average temperature in Jeju over the whole year is 16°C. August is the hottest month, with highs of about 30°C; January is the coldest, with lows of about 6°C. Jeju has no sharply defined rainy season: the chance of rain on a given day runs from 44% in October, the driest month, to 61% in July, the wettest. Winds in Jeju are highest in January, averaging 4.3 m/s (15 km/h), and lightest in June, at 3.3 m/s (12 km/h). The prevailing wind is from the N. The clearest skies in Jeju come in August, when the sky is typically 62% covered; December is the cloudiest month, at 78%.
Month by month Jeju climate by month: average temperatures year round · click a month to read it
| Month | High | Low | Feels like | Chance of rain | Cloud | Wind | Being outside | Sun | Walking |
|---|---|---|---|---|---|---|---|---|---|
| January | 8°C | 6°C | 3°C | 48% | 78% | 4.3 m/s | 1 | 0 | 23 |
| February | 8°C | 6°C | 3°C | 55% | 75% | 4.3 m/s | 3 | 0 | 27 |
| March | 13°C | 9°C | 8°C | 53% | 66% | 4.0 m/s | 11 | 0 | 56 |
| April | 17°C | 13°C | 13°C | 58% | 66% | 3.8 m/s | 39 | 0 | 79 |
| May | 21°C | 16°C | 18°C | 59% | 68% | 3.4 m/s | 75 | 6 | 74 |
| June | 24°C | 21°C | 24°C | 60% | 72% | 3.3 m/s | 75 | 33 | 40 |
| July | 29°C | 26°C | 30°C | 61% | 72% | 3.8 m/s | 22 | 52 | 6 |
| August | 30°C | 27°C | 32°C | 57% | 62% | 3.7 m/s | 10 | 46 | 2 |
| September | 26°C | 23°C | 26°C | 56% | 73% | 4.2 m/s | 59 | 43 | 26 |
| October | 21°C | 18°C | 19°C | 44% | 67% | 3.9 m/s | 71 | 9 | 72 |
| November | 16°C | 12°C | 12°C | 55% | 67% | 3.9 m/s | 34 | 1 | 72 |
| December | 10°C | 7°C | 5°C | 48% | 78% | 4.3 m/s | 4 | 0 | 37 |
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Jeju weather by season
Year round, Jeju has days of about 8°C at their warmest in January, its coolest month, and 30°C in August, its warmest; the coolest hours of the day run from 6°C to 27°C through the year, and the average temperature over the year is 16°C around the clock. Rain is most likely around July and least likely around October. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Jeju weather in winterDecember to February
Winter in Jeju has typical daily highs of about 9°C and lows of about 6°C, with a 50% chance of rain on a given day.
Jeju weather in springMarch to May
Spring in Jeju has typical daily highs of about 17°C and lows of about 13°C, with a 57% chance of rain on a given day.
Jeju weather in summerJune to August
Summer in Jeju has typical daily highs of about 27°C and lows of about 24°C, with a 59% chance of rain on a given day.
Jeju weather in autumnSeptember to November
Autumn in Jeju has typical daily highs of about 21°C and lows of about 18°C, with a 52% chance of rain on a given day.
When is the rainy season in Jeju?
Jeju has no sharply defined rainy season: the chance of rain on a given day runs from 44% in October, the driest month, to 61% in July, the wettest.
What time of year is Jeju windiest?
Winds in Jeju are highest in January, averaging 4.3 m/s (15 km/h), and lightest in June, at 3.3 m/s (12 km/h). The prevailing wind is from the N.
What is the average temperature in Jeju year round?
The average temperature in Jeju over the whole year is 16°C. August is the hottest month, with highs of about 30°C; January is the coldest, with lows of about 6°C.
Where to go instead in early February, the weakest time here for being outside
How this is worked out
Every figure is a decade of weather-station observations blended into one typical year, in ten-day sections. The ratings, the chart and the feels-like column are read at midday local solar time. Being outside is the Easy outdoors rating, Sun is Sunbathing and Walking is Active outdoors, each out of 100: Good from 55, Ideal from 80. They describe what a time of year is usually like here, not a forecast. The dotted links open the map at that time of year; set its time of day to midday to see these numbers.