Korea in October: Two Long Weekends Decide Your Trip More Than the Weather Does

Two long weekends. Six days. They will do more to your hotel bill than the forecast will.

3–5 October and 9–11 October are both three-day weekends here this year, and on those six days the trains fill, the coastal towns fill, and the prices follow. Pick your dates around them and the same trip costs less and feels emptier. Pick your dates on top of them and you will spend the holiday queuing with everyone else.

That is the part the weather posts leave out. Korea in October really is the month people recommend — but which October week you choose matters more than the average temperature, and the average temperature is misleading anyway.

October is not one temperature

The month is a slope, not a plateau.

That matters because packing advice usually gets written from a single number, and the single number hides a ten-degree swing inside every day. Using the Korea Meteorological Administration's 1991–2020 climate normals for Seoul, the average daily high is 20.2°C and the average low is 10.6°C, around a daily mean of 15.0°C.

The month-to-month drop is even sharper than the daily one.

Month	Average daily temperature (Seoul, 1991–2020 normals)
September	21.7°C
October	15.0°C
November	7.5°C

An early-October afternoon can feel like late summer. A late-October morning does not. If you are coming for two weeks that straddle the month, you are effectively packing for two seasons.

The upside is real, though, and it is why people keep recommending this month: October averages 52.2 mm of rain across about 6.1 rainy days, with 206.5 hours of sunshine. It is one of the driest, clearest stretches of the Korean year.

So if the weather is the good news, what is the catch?

The catch is the calendar, not the climate

There are two public holidays this month, and both of them make three-day weekends this year.

National Foundation Day falls on Saturday 3 October. Because it lands on a weekend, Korean law grants a substitute holiday, which moves the day off to Monday 5 October — so 3 to 5 October is a three-day weekend. Hangul Day then falls on Friday 9 October, giving a second three-day weekend from 9 to 11 October.

Those are the two blocks when Koreans travel domestically. KTX seats, coastal guesthouses and popular restaurants go first, and they go early.

Dates	What it is	What it means for you
3–5 Oct (Sat–Mon)	National Foundation Day + substitute Monday	Domestic travel peak
6–8 Oct (Tue–Thu)	Ordinary weekdays	The quietest window of the month
9–11 Oct (Fri–Sun)	Hangul Day weekend	Second domestic travel peak
12 Oct onward	Ordinary weeks	Prices normalise, foliage strengthens

One thing worth clearing up: Chuseok is not in October this year. It runs 24 to 26 September, with the Sunday making it four days — and an empty Seoul during Chuseok is genuinely one of the best times to be in the city, which is a different argument for a different set of dates.

If the dates matter that much, which ones should you actually book?

How to choose your dates

Aim at the middle of the month.

The reason is simply arithmetic: the two holiday blocks sit at the start of the month, so from roughly 12 October the country goes back to work and the leaves keep improving for another three weeks. The better foliage and the smaller crowds end up in the same fortnight.

Three practical rules for Korea in October:

Book intercity travel before you fly if any part of your trip touches 3–5 or 9–11 October. Those seats sell out while overseas visitors are still deciding.
Pack a real jacket, not just a layer. The morning you leave at 8am in late October is closer to 10°C than to 20°C.
Do not chase peak foliage by date. It moves north to south over several weeks, which is why picking the latitude beats picking the dates.

If mountains are the point of the trip, late October is when the north-east is at its best, and the entrance you pick at Seoraksan decides your whole day — that one is worth reading before you book anything.

What the month actually looks like

Clear skies, hard mornings, and a country that is outdoors.

This is the season of school trips, company outings and weekend hiking, so trails and parks are busier than in summer even outside the holidays. It is also the last comfortable month: by mid-November the average drops to 7.5°C and the season is over.

If you want one sentence to plan around, it is this. Come now, avoid the first eleven days if you can, and bring something with sleeves.

FAQ

What is the weather like in Korea in October?

Mild and dry. Seoul averages a daily high of 20.2°C and a low of 10.6°C, with about 52.2 mm of rain over roughly 6 rainy days and 206.5 hours of sunshine, based on Korea Meteorological Administration normals.

Are there public holidays in October 2026?

Two. National Foundation Day on Saturday 3 October, with a substitute holiday on Monday 5 October, and Hangul Day on Friday 9 October. Both create three-day weekends.

Is Chuseok in October?

Not this year. Chuseok runs 24 to 26 September 2026, so it is finished before the month begins.

When is the best week to visit?

Mid-month onwards, from about the 12th. The holiday crowds have gone and the autumn colour is still improving.

Next: where the colour actually is

Korea in October is two three-day weekends, a ten-degree daily swing, and the last warm weeks of the year. Choose the middle of the month, book anything intercity early, and carry a jacket you would actually wear.

The one question this leaves open is where to go once you have the dates — because autumn does not arrive everywhere at once, and the answer is further north than most itineraries assume. That is the next thing to work out before you book.

References

Korea Meteorological Administration — climate normals, 1991–2020 — Seoul monthly temperature, precipitation and sunshine figures
Korea Law Information Centre — Act on Public Holidays and its substitute-holiday provision
Seoul climate summary table, sourced from KMA normals — monthly comparison