Seoul capital, city break
Best months: April, June, September to October. Rainiest: July to August. Highs range from 36°F (2°C) to 85°F (29°C).
Best Time to Visit South Korea
The best time to visit South Korea: in Seoul, April, June, September to October. The wettest stretch on Jeju is July, August, September. It is hottest on Jeju in August, with highs of 85°F (30°C). It is coolest in Seoul in January, with highs of 36°F (2°C). The sea is warmest on Jeju in August, at 86°F (30°C).
Climate normals were checked on September 29, 2026, over a year ago. An update is due.
Climate normals checked September 29, 2026 · Source: Open-Meteo (ERA5) · How we calculate
South Korea weather by month
Colour shows the month rating for the best region. See the table below for month-by-month details.
- Jan36°FJanuary: Off-season
- Feb41°FFebruary: Off-season
- Mar53°FMarch: Off-season
- Apr64°FApril: Good
- May73°FMay: Mixed
- Jun81°FJune: Good
- Jul83°FJuly: Mixed
- Aug84°FAugust: Mixed
- Sep78°FSeptember: Good
- Oct65°FOctober: Good
- Nov59°FNovember: Off-season
- Dec38°FDecember: Off-season
Excellent Good Mixed Off-season
South Korea air and sea temperature by month
- Seoul: air
- Busan: air
- Busan: sea
- Jeju: air
- Jeju: sea
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Seoul: air | 36 | 41 | 53 | 64 | 73 | 81 | 84 | 85 | 78 | 65 | 52 | 38 |
| Busan: air | 44 | 47 | 55 | 62 | 70 | 75 | 81 | 84 | 77 | 69 | 59 | 47 |
| Busan: sea | 55 | 54 | 55 | 58 | 63 | 70 | 75 | 83 | 81 | 73 | 65 | 59 |
| Jeju: air | 46 | 48 | 56 | 63 | 71 | 76 | 83 | 85 | 78 | 69 | 61 | 50 |
| Jeju: sea | 61 | 59 | 58 | 60 | 64 | 71 | 80 | 86 | 84 | 78 | 70 | 65 |
South Korea weather table, month by month
Long-term averages for each region. Tap a region to open its table.
Seoul · capital, city break
| Month | Day high | Night low | Rainy days | Rainfall | Humidity | Sun, h/day |
|---|---|---|---|---|---|---|
| January | 36°F (2°C) | 20°F (−7°C) | 3 | 0.7 in (18 mm) | 58% | 7.8 |
| February | 41°F (5°C) | 23°F (−5°C) | 4 | 1.0 in (26 mm) | 61% | 8.4 |
| March | 53°F (12°C) | 32°F (0°C) | 6 | 1.6 in (40 mm) | 66% | 9.1 |
| April | 64°F (18°C) | 43°F (6°C) | 7 | 2.5 in (64 mm) | 65% | 9.3 |
| May | 73°F (23°C) | 53°F (12°C) | 8 | 4.2 in (106 mm) | 68% | 10.0 |
| June | 81°F (27°C) | 63°F (17°C) | 10 | 4.8 in (121 mm) | 72% | 9.8 |
| July | 84°F (29°C) | 71°F (22°C) | 18 | 12.2 in (310 mm) | 82% | 8.2 |
| August | 85°F (29°C) | 72°F (22°C) | 16 | 10.2 in (260 mm) | 82% | 9.2 |
| September | 78°F (25°C) | 63°F (17°C) | 9 | 5.2 in (131 mm) | 77% | 8.6 |
| October | 65°F (19°C) | 48°F (9°C) | 6 | 3.0 in (76 mm) | 74% | 8.3 |
| November | 52°F (11°C) | 35°F (2°C) | 7 | 2.3 in (59 mm) | 71% | 7.2 |
| December | 38°F (3°C) | 22°F (−5°C) | 4 | 1.0 in (26 mm) | 63% | 7.2 |
Busan · Haeundae beach
| Month | Day high | Night low | Sea | Rainy days | Rainfall | Humidity | Sun, h/day |
|---|---|---|---|---|---|---|---|
| January | 44°F (7°C) | 30°F (−1°C) | 55°F (13°C) | 4 | 1.7 in (44 mm) | 59% | 7.7 |
| February | 47°F (9°C) | 33°F (0°C) | 54°F (12°C) | 6 | 2.2 in (55 mm) | 60% | 8.4 |
| March | 55°F (13°C) | 40°F (5°C) | 55°F (13°C) | 8 | 3.8 in (97 mm) | 67% | 8.6 |
| April | 62°F (17°C) | 49°F (9°C) | 58°F (14°C) | 8 | 5.2 in (131 mm) | 71% | 8.8 |
| May | 70°F (21°C) | 57°F (14°C) | 63°F (17°C) | 8 | 4.5 in (115 mm) | 74% | 9.7 |
| June | 75°F (24°C) | 65°F (18°C) | 70°F (21°C) | 11 | 7.6 in (193 mm) | 82% | 8.9 |
| July | 81°F (27°C) | 73°F (23°C) | 75°F (24°C) | 16 | 11.3 in (286 mm) | 88% | 8.4 |
| August | 84°F (29°C) | 75°F (24°C) | 83°F (28°C) | 15 | 8.4 in (213 mm) | 84% | 9.9 |
| September | 77°F (25°C) | 68°F (20°C) | 81°F (27°C) | 12 | 10.5 in (267 mm) | 81% | 7.7 |
| October | 69°F (20°C) | 57°F (14°C) | 73°F (23°C) | 6 | 3.7 in (94 mm) | 72% | 8.2 |
| November | 59°F (15°C) | 45°F (7°C) | 65°F (18°C) | 5 | 2.1 in (53 mm) | 68% | 7.9 |
| December | 47°F (8°C) | 33°F (0°C) | 59°F (15°C) | 4 | 1.4 in (36 mm) | 61% | 7.8 |
Jeju · volcanic island
| Month | Day high | Night low | Sea | Rainy days | Rainfall | Humidity | Sun, h/day |
|---|---|---|---|---|---|---|---|
| January | 46°F (8°C) | 37°F (3°C) | 61°F (16°C) | 14 | 3.9 in (100 mm) | 75% | 5.3 |
| February | 48°F (9°C) | 38°F (3°C) | 59°F (15°C) | 12 | 3.5 in (90 mm) | 73% | 6.3 |
| March | 56°F (13°C) | 44°F (6°C) | 58°F (14°C) | 12 | 4.9 in (125 mm) | 74% | 7.9 |
| April | 63°F (17°C) | 51°F (11°C) | 60°F (16°C) | 11 | 5.5 in (139 mm) | 75% | 8.7 |
| May | 71°F (22°C) | 59°F (15°C) | 64°F (18°C) | 11 | 5.8 in (148 mm) | 75% | 9.2 |
| June | 76°F (24°C) | 67°F (19°C) | 71°F (22°C) | 14 | 8.7 in (221 mm) | 84% | 8.0 |
| July | 83°F (28°C) | 75°F (24°C) | 80°F (26°C) | 18 | 9.7 in (247 mm) | 87% | 8.5 |
| August | 85°F (30°C) | 77°F (25°C) | 86°F (30°C) | 17 | 9.4 in (238 mm) | 84% | 10.4 |
| September | 78°F (26°C) | 71°F (22°C) | 84°F (29°C) | 17 | 14.0 in (356 mm) | 84% | 7.8 |
| October | 69°F (20°C) | 61°F (16°C) | 78°F (25°C) | 11 | 6.5 in (164 mm) | 77% | 8.0 |
| November | 61°F (16°C) | 51°F (10°C) | 70°F (21°C) | 11 | 4.6 in (116 mm) | 76% | 6.6 |
| December | 50°F (10°C) | 41°F (5°C) | 65°F (18°C) | 13 | 3.4 in (87 mm) | 74% | 5.1 |
Best time to visit South Korea for beaches, sightseeing and savings
| Goal | When to go |
|---|---|
| Beach holiday | Busan: August to September (often rainy) Jeju: July to September (often rainy) |
| Sightseeing | Seoul: April, October Busan: October |
| Peak season | April, June, September to October |
| Cheaper: shoulder season | May, July to August |
- Beach holiday — sea 75°F (24°C)+, highs 75–95°F (24–35°C), rain under 150 mm
- Sightseeing — highs 63–88°F (17–31°C), rain under 100 mm
- Peak season — the best weather rating of the year
- Cheaper: shoulder season — months next to peak season, weather still decent
Shoulder season is a weather-based estimate, not a price check: demand is lower in these months, so flights and hotels are usually cheaper than at peak. We do not compare prices here; check them for your dates.
- Compare with other destinations: where to go in April, where to go in June, where to go in September, where to go in October.
How to use it
- Read the calendar: green is in season, red is off-season.
- Open a region table for highs and lows, sea temperature, rainfall, rainy days, humidity and sunshine.
- Pick your goal in the “When to go” block: beach, sightseeing or shoulder season.
- Compare with other destinations in “Where to go” for your month.
When to visit each region of South Korea
Busan Haeundae beach
Rainiest: July to September. Highs range from 44°F (7°C) to 84°F (29°C), sea 54–82°F (12–28°C).
Jeju volcanic island
Rainiest: June to September. Highs range from 46°F (8°C) to 85°F (30°C), sea 57–86°F (14–30°C).
Best time to visit South Korea: FAQ
When is the best time to visit South Korea?
The best time to visit South Korea: in Seoul, April, June, September to October. The wettest stretch on Jeju is July, August, September. It is hottest on Jeju in August, with highs of 85°F (30°C). It is coolest in Seoul in January, with highs of 36°F (2°C). The sea is warmest on Jeju in August, at 86°F (30°C).
What is South Korea's rainy season?
Months with more than 200 mm (7.9 in) of rain: in Seoul, July to August; in Busan, July to September; on Jeju, June to September. The wettest month on Jeju is September, with about 14.0 in (356 mm).
Is South Korea hot all year?
Day highs in Seoul range from 36°F (2°C) to 85°F (29°C). The hottest month is August on Jeju, at 85°F (30°C).
Where the data comes from
- Air temperature, rainfall, humidity — ERA5 reanalysis (Copernicus / ECMWF) via Open-Meteo, averaged over 2015–2024. Each region uses one point: the resort or city in its caption.
- Sea temperature — Open-Meteo Marine, average sea surface temperature for 2023–2026 (the source has no longer record yet).
- Sunshine — sunshine duration from the same ERA5 reanalysis (Open-Meteo), average hours of sun per day for the month, 2015–2024.
- Rainy days — days with at least 1 mm (0.04 in) of rain. Reanalysis picks up light rain more often than weather stations, so treat this as an upper bound.
- Month rating — one rule for every destination, based on three factors: day highs (ideal 75–91°F / 24–33°C), monthly rainfall (ideal under 80 mm / 3.1 in) and, for beach regions, sea temperature (ideal 77°F / 25°C or warmer). All ideal means Excellent; one slightly weaker factor means Good. Mixed means heavy rain (150 mm / 5.9 in or more), highs above 97°F (36°C) or a sea below 70°F (21°C). Off-season means highs of 100°F (38°C) or more, cold below 54°F (12°C), over 350 mm (13.8 in) of rain, or several problems at once. A country's rating follows its best region, so check the regional table.
- Licence — weather data by Open-Meteo.com under CC BY 4.0; ERA5 reanalysis by the Copernicus Climate Change Service / ECMWF. The normals are precomputed and stored on this site, so the page sends no requests to the source.
Checked September 29, 2026. Climate normals are refreshed yearly and the notes every 90 days. These are long-term averages, not a forecast: any given year can differ.
