Weather in Seoul in August

Shoulder season. August sits in between. You will get good days and you will lose some. You should expect rain on 17 days of the month, which is more days wet than dry.

August ranks 8 of 12 in Seoul: past the worst of the year but short of May, which is the month to book if the dates are open.

This is wet-season rain: 17 wet days and 7 genuinely heavy ones, which in this climate means concentrated downpours rather than all-day grey. The pattern is usually a clear morning and a loud afternoon, so front-load the day and stop fighting the 3pm hour. Natural fibres and a second shirt for the day. At 83% nothing dries, including you.

What the averages hide

Averages flatten a month, and this one hides a few things: 7 days top 30 °C — hot spells arrive, but they break. Across the twenty years measured, the hottest August day reached 35.6 °C and the coldest night fell to 14.6 °C, and the wettest single day dropped 135 mm — roughly 52% of the month's rain in one day.

August is moderately variable: 64 mm in the driest year against 578 mm in the wettest, around an average of 260 mm. Roughly two Augusts in three land near that average, and the third does something else entirely.

Wind is light at 9.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 83%, high enough to notice on the warm days without dominating them.

How August sits in the year

Temperatures hold steady either side: 27.7 °C in July, 28.5 here, 24.7 in September. Nothing about the timing within the month matters much. Rain is the thing that moves: September brings 7 days less of it, so pushing the dates later buys drier weather.

Daylight in August

13.7 hours of daylight, losing 1 hours across the month. That is between Seoul's extremes of 14.7 and 9.6 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 35.2 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

August in Seoul versus nearby

If Seoul is one option among several, the nearby comparison is worth making. Daegu is the weaker option in August — within a degree on temperature, 1 day less rain. Gwangju is close enough to be a coin toss — within a degree on temperature, 1 day less rain.

So: August is a compromise. May is 27 points better and is what Seoul is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Seoul

See all twelve months in Seoul, or where else to go in August.