Mild
Average highs are around 26°C, so days are mild rather than hot.
September verdict
Seoul, South Korea in September
Weather score61Good
Good for holiday weather
Average highs are around 26°C, so days are mild rather than hot. Sunshine averages 6.6h per day, enough for a balanced month. Rainfall averages 161mm, so some wet days are possible.
September weather
Monthly averages
Temp
26°C
Rain
161mm
Sun
6.6h
Sea
23°C
Weather score
61
Good
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 161mm, so some wet days are possible.
Some sun
Sunshine averages 6.6h per day, enough for a balanced month.
Swimmable
Sea temperatures average 23°C, which can work for swimming but may feel fresh.
Map
Weather map
Compare Seoul, South Korea with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
September26°C average high
September sits in the warmer part of the year, so midday sightseeing can feel heavier than in cooler months.
Warmest monthsMay to September
This stretch sets the upper range for average daytime heat.
Rain
September161mm average rain
September sits near Seoul's yearly rainfall average, so rain is a normal planning factor rather than an outlier.
Driest monthsJanuary to June and October to December
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
September6.6 hours average sun
September sits close to Seoul's yearly sunshine average, so it is a middle-of-the-pack month for bright days.
Brightest monthsApril to June
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
September23°C average sea
September is one of Seoul's warmest sea months, when swimming comfort is usually strongest.
Warmest seaJuly to October
Sea temperatures are usually near 20°C in this stretch, so swimming comfort is at its strongest.
Weather score
September61 weather score
September is one of Seoul's best weather-score months, combining the strongest overall balance in the yearly averages.
Best weather monthsJune and September
These months have the strongest weather score in the monthly averages.
Hotels in Seoul, South Korea
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