Busan weather in September

September in Busan: hot, soaked, with clean air — fine if you can take 13 rainy days.

Updated September 2026 · climate normals from ERA5 reanalysis

Busan🇰🇷 South Korea · Korea · City65
  1. 66Jan
  2. 69Feb
  3. 74Mar
  4. 81Apr
  5. 88May
  6. 77Jun
  7. 61Jul
  8. 58Aug
  9. 65Sep
  10. 86Oct
  11. 82Nov
  12. 70Dec

#10 of 12 months in Busan · #1036 of 1413 destinations to visit in September · comfort 65/100 (tier C)

Days
27°C
Nights
21°C
Wet days
13
Sun
7.6 h
Humidity
79%
Daylight
12 h
Busan, South Korea
Photo: Jhany Blue · Pexels

Traveller notes on Busan in September

Other months in Busan

Regulars are consistent that this city runs genuinely warmer than Seoul at the same time of year, though they're quick to add that doesn't mean actually warm - wind can pick up and make a sunny day feel colder than the number suggests. Our row backs that cold, still-mild-for-Korea read, 10.2C over 1.7C nights feeling -2C, with 27.9mm of rain across 3.5 days and a trace of snow, 0.2cm. Regulars are consistent indoor spaces generally have good heating, so the real discomfort comes from walking between destinations rather than time spent inside. A proper padded jacket is the standard packing advice regardless of how mild the forecast looks by Seoul standards. The sea sits at a cold 15.2C. The record: humidity 57 percent, 7.8 hours of sun, an 18 kph wind and AQI 55.
WarmerThanSeoulButDontCallItWarm · December · 1 month ago · Read more on Tripadvisor ↗
March here is two seasons inside one day - winter in the morning and at night, warm by the afternoon - and Korean has a word for the particular cold snap that arrives near the end of winter, kkotsaemchuwi, the cold that envies the flowers. Our row carries the bite: 14.5C by day but 12C to stand in, 6.4C nights that feel like 3C in a 19 kph wind. On blossom the board is consistent - the trees here open in late March, the Jinhae festival an hour to the west runs from about then into early April, and anyone arriving early in the month is too early. Rain is 86.3mm across 7.6 days, with 1.5cm still in the snow column and a 13.8C sea. The record: humidity 66 percent, 8.8 hours of sun and AQI 76.
TheColdThatEnviesTheFlowers · March · 1 month ago · Read more on Tripadvisor ↗
June splits around the jangma, the Korean rainy season, which regulars put at roughly mid-June through to some point in July - and they are careful that the dates move and the rainfall is hard to predict. It can come down heavily all day, then break; it can rain one day and be dry the next. Our row reads 163.2mm across 10.5 days, sixteen millimetres apiece, which is that pattern rather than a drizzle. The compensation is the beaches: the peak here is late July into August, so June is the quiet half of the summer, with 25.3C air and a 21.2C sea. The record: 19.4C nights, humidity 83 percent, 9.3 hours of sun and AQI 73.
JangmaArrivesMidMonth · June · 1 month ago · Read more on Tripadvisor ↗
November in Busan is the gap between the seasons - the autumn leaves are finishing and the snow has not started - and regulars describe the late-autumn south coast as not that cold, warm enough that winter clothes are unnecessary. Our row gives 17.4C days reading as 15C over 8.9C nights. The caveat they add is Korean winter's habit of arriving in bursts: a Siberian air mass can drop a week hard, and one visitor's late-November fortnight ran 8 to 10C by day and below freezing before dawn. So: layers, with something properly warm in the bag for a cold snap that may never come. It is also a dry month here, 43.6mm across 3.7 days. The record: humidity 63 percent, 8.1 hours of sun and a 17.7C sea.
BetweenAutumnAndWinter · November · 1 month ago · Read more on Tripadvisor ↗

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Busan climate normals — September

Daytime high27°C / 80°F🥵 hot
Nighttime low21°C / 69°F
Feels like (high)30°C / 86°F
Sea temperature27°C / 80°F😎 warm sea
Rainfall237 mm / 9.3 in⛈ soaked
Rainy days13 days
Humidity79%💦 very humid
Dew point18°C / 65°F
Sunshine7.6 h/day
Daylight12.4 h
Wind18 km/h / 11 mph
Air quality (US AQI)47🍃 good

Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.

Crowds in Busan in September

How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.

Peak crowdsChuseok, Chuseok in South Korea, school holidays in 2 of the markets that fill it(estimated)

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Peak crowdsBusyShoulder seasonQuiet

Best months for Busan's weather

Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).

Toughest weatherBusan's best weather comes in May, October and November — separate windows, not one continuous season.

September coincides with Typhoon season.

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Best weatherFair weatherToughest weather

What's on in Busan in September

Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.

  • Hazard

    Typhoon season

    1 Aug – 30 Sep · usuallyClosures

    Busan takes the brunt of the systems that reach Korea. A landfall closes the port, floods Gwangalli and stops the trains for a day. Source ↗

  • Holiday

    Chuseok

    24–26 SepHarvestClosuresCrowded

    The harvest holiday empties the city for three days; markets and family restaurants close and the roads and trains out are solid in both directions. Source ↗

What's on around the world in September →

Nearby, and something's on

Within 300 km of Busan — a day trip or a short hop — with something on this month. Never part of the comfort score.

Where is Busan?

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Busan in September — FAQ

Is September a good time to visit Busan?
September in Busan: hot, soaked, with clean air — fine if you can take 13 rainy days. It ranks #10 of 12 months for Busan on SeasonMap's comfort score (65/100).
What is the weather like in Busan in September?
In September, Busan averages a daily high of 26.9°C and a low of 20.8°C, with about 237 mm of rain over roughly 12.7 rainy days.
What is the air quality in Busan in September?
Busan has a mean US Air Quality Index of about 47 in September.

Within 300 km: Jeju's Hallasan summit permits on 1 Jan – 31 Dec.