Will I be hot?
Will I be hot in Seoul in September?
Verdict
Maybe — Warm at times.
Highs around 79°F — comfortable in shade, warm in direct sun.
Day vs. night
Day
79°F
Warm
Breathable fabrics; sunscreen matters more than a jacket.
Night
63°F
Comfortable
Comfortable outside without an extra layer.
Why
Seoul in September averages highs of 79°F, lows of 63°F, 10 rainy days.
Bring a light layer for the shade and a hat for the sun — the difference between them can feel like 15°F.
See a full outfit plan for warm afternoons →
Seoul in September outfit ideas from ForecastStyle.