Verdict: Fair month
Jeju Weather in August
August runs warm in Jeju, with daily highs around 30°C (86°F) and nights near 25°C (77°F). It's also the wet side of the calendar: rain falls on about 19 days, so build flexibility into plans. August is workable in Jeju if your dates are fixed — just plan around the conditions.
Average high
30°C / 86°F
Average low
25°C / 77°F
Rain days
~19
Precipitation
228 mm
What to pack for Jeju in August
- Light, breathable clothing — linen and technical fabrics earn their keep
- High-SPF sunscreen, sunglasses, and a refillable water bottle
- Rain gear is non-negotiable — expect rain on roughly 19 days
- Comfortable walking shoes — every guide on this site assumes you'll use them
August against the rest of the year
Warmest in Jeju: Aug (30°C / 86°F) · Coolest: Jan (8°C / 46°F) · Wettest: Jul (~20 rain days)
8°
3°
Jan
10°
4°
Feb
14°
7°
Mar
17°
11°
Apr
22°
15°
May
25°
20°
Jun
29°
24°
Jul
30°
25°
Aug
26°
22°
Sep
21°
16°
Oct
16°
11°
Nov
9°
5°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)