Seoul vs Jeju

Based on sunshine hours, rain days, comfortable temperatures, and humidity levels, Seoul edges ahead as the better destination in September. Seoul offers 8 hours of daily sunshine with only 8 rain days, while Jeju sees 8 sunshine hours and 13 rain days.

Seoul sits in the comfortable travel range at 25°C. Jeju is also comfortable at 25°C.

For travelers who prioritize dry weather, Seoul is the stronger choice in September.

Seoul reaches an average high of 25°C (77°F) and drops to 16°C (61°F) at night during September. The daily temperature range is 9°C, meaning moderate variation throughout the day.

Jeju averages 25°C (77°F) for the high and 22°C (72°F) for the low, with a daily range of 3°C. The two cities feel quite similar in terms of temperature.

Both cities are in the Northern Hemisphere, so they share the same seasonal pattern in September.

Seoul receives approximately 123 mm of rainfall across 8 rain days during September. You can expect rain roughly every other day.

Jeju sees 188 mm over 13 rain days. That makes Seoul the drier option by 5 rain days and 65 mm of total precipitation.

Humidity also differs: Seoul averages 65% while Jeju sits at 70%. Jeju will feel muggier, especially at higher temperatures.