Seoul Weather in September: Climate, Temperature & Travel Tips
Avg 22.0°C · 156mm rain — September is autumn in Seoul.
- Avg high
- 26.1 °C
- Avg low
- 17.8 °C
- Avg
- 22.0 °C
- Precipitation
- 156 mm
Source: Open-Meteo Archive 2014–2023 · 10-year climate normals
Climate Overview
September in Seoul, South Korea brings autumn conditions: average temperature 22.0°C, average high 26.1°C, average low 17.8°C. Monthly rainfall averages 156mm, making it a wet time of year.
Conditions are pleasant for most travel activities.
What to Pack
- Short sleeves and light pants; sunglasses
- Light shoes or sandals
- Compact umbrella and waterproof jacket
Best Things to Do
- Walking tours and city exploration
- Parks and outdoor cafes
- Seasonal food and night markets (where applicable)
Pros and Cons of Visiting in September
Pros:
- Pleasant temperatures for walking and outdoor sightseeing
- Shoulder season often means smaller crowds and lower prices
Cons:
- Frequent rain — pack waterproof gear
Climate source: Open-Meteo Archive (2014–2023).
Colour = avg temperature · blue = cool · orange = warm
- 1 August 26.6°C
- 2 July 25.4°C
- 3 June 23.2°C
- 1 January -1.8°C
- 2 December 0.2°C
- 3 February 1.2°C
FAQ
01 What is the average temperature in Seoul in September? +
The average is 22.0°C, with a high of 26°C and a low of 18°C.
02 What is Seoul like to visit in September? +
It is autumn in Seoul, which is ideal for outdoor exploration.
03 Does it rain often in Seoul during September? +
Average rainfall is 156mm, which is high — expect frequent rain.
04 What should I pack for Seoul in September? +
Short sleeves and light pants; sunglasses; Light shoes or sandals.
05 Is September a peak travel season for Seoul? +
It is closer to off-season, with more reasonable prices and fewer crowds.
06 Where does this climate data come from? +
Monthly averages computed from Open-Meteo Archive 2014–2023 daily observations.
- Sources
- Open-Meteo Archive 2014-2023
- Updated
- 2026-04-17