Measurements:
°C
°F
Jeju
68°F
SE 7 mph
Feels like: 68°F
Precip: 7%
World Resorts South Korea Jeju Weather

Jeju Sea Water Temperature

Current Sea Water Temperature:
+80.2°F
Maximum Sea Water Temperature in September: 89.6°F
Minimum Sea Water Temperature in September: 72.2°F
Average water temperature in September: 80.6°F

Sea Water Temperature for the Last 10 Days:

September 28 80.2°F September 23 79.8°F
September 27 79.4°F September 22 81.4°F
September 26 79.8°F September 21 81.4°F
September 25 80.2°F September 20 80.6°F
September 24 80.0°F September 19 80.2°F

When is the Warmest Sea for Jeju?

According to our data for the last three years for Jeju the highest average sea water temperature was in August, September and July.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Jeju was 86.1°F. The maximum and minimum values were 82.2°F and 89.8°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Jeju was 82.5°F. The maximum and minimum values were 79.4°F and 89.0°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Jeju was 81.4°F. The maximum and minimum values were 74.6°F and 90.0°F respectively.

Best Time to Visit Jeju
The most sunny months:
May 15 days
October 14 days
April 14 days
The most warm months:
August 88.3 °F
July 85.7 °F
September 80.6 °F
Warmest sea temperature:
August 84.8 °F
September 80.6 °F
July 79.6 °F
The most cold months:
January 44.2 °F
February 45.9 °F
December 48.5 °F
The most rainy months:
August 8 days
July 7 days
September 6 days
The most windy months:
January 14 mph
December 14 mph
February 14 mph

Jeju on the Weather Map

South Korea Resorts:
NAME
F°
Busan +74
Incheon +66
Jeju +68
Muju +60
Seoul +64
Yongpyong +56
24 Hours Weather Forecast
Jeju
Local time: 06:16
29 sep, tuesday
0900 70°F
S
8 mph
1200 72°F
S
8 mph
1500 74°F
S
7 mph
1800 72°F
S
4 mph
2100 70°F
SW
5 mph
30 sep, wednesday
0000 72°F
SW
5 mph
0300 70°F
W
5 mph
0600 70°F
NW
5 mph