Jeju Weather in September
South Korea · 30-year monthly averages
🤔 Fair time to visit
September in Jeju is warm, with average daytime highs around 26°C (79°F) and nighttime lows near 21°C (70°F). Expect roughly 228mm of precipitation spread over about 8 rainy days, and heavy rainfall is common — this is peak wet season territory.
Avg high
26°C
79°F
Avg low
21°C
70°F
Rainfall
228mm
very wet
Rainy days
8
days with ≥1mm
☀️ About 159 hours of sunshine over the month (~5h/day).
🎒 What to pack
- light summer clothing
- sunscreen and sunglasses
- compact umbrella or rain jacket
September vs the rest of the year
FAQ
- How hot is Jeju in September?
- September in Jeju is warm, with average daytime highs around 26°C (79°F) and nighttime lows near 21°C (70°F). Expect roughly 228mm of precipitation spread over about 8 rainy days, and heavy rainfall is common — this is peak wet season territory.
- Does it rain a lot in Jeju in September?
- Jeju sees around 228mm of precipitation in September on average — very wet by global standards.
- Is September a good time to visit Jeju?
- September is a workable month to visit Jeju, but expect some weather trade-offs.