Average sea water temperature in September:
+77.5°F
| Minimum sea water temperature in September: | 85.6°F |
| Maximum sea water temperature in September: | 70.0°F |
Daily sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 82.5°F. The highest and lowest sea temperatures during the month were 85.6°F and 77.9°F.
Monthly sea water temperature in Jeju, °F
Which South Korea resorts have warmest sea in September?
| Place name | September 2025 | September 2024 |
|---|---|---|
| Jeju | 82.5°F | 82.6°F |
| Incheon | 78.3°F | 80.1°F |
| Busan | 77.8°F | 81.6°F |
| Seoul | 76.6°F | 78.3°F |
| Yongpyong | 76.5°F | 76.1°F |
Best time for vacation in Jeju
Jeju on a weather map
Places in South Korea:
Name
°F
24 Hours Forecast
Jeju
Local time: 04:07
May 18, monday
0600

63°F
NW
4 mph
4 mph
0900

72°F
SE
4 mph
4 mph
1200

75°F
S
5 mph
5 mph
1500

77°F
S
5 mph
5 mph
1800

73°F
S
4 mph
4 mph
2100

68°F
N
4 mph
4 mph
May 19, tuesday
0000

66°F
NW
2 mph
2 mph
0300

64°F
N
4 mph
4 mph

























