Rainy Season in Seoul — When It Is & What to Expect
Seoul has a distinct rainy season covering May to September, when roughly 1194mm of rain falls — the bulk of the annual total. The wettest month is August (401.9mm over about 20 rainy days). Outside these months rainfall drops sharply, which is why the best time to visit is All year.
Seoul — Monthly Rainfall
Average monthly rainfall in millimetres, calculated from 2020–2023 data. Highlighted bars mark the rainy season.
Rainfall in Seoul month by month
| Month | Rain | Rainy days | High | Rating |
|---|---|---|---|---|
| January | 30.6mm | 4 | 2.4°C | 8/10 |
| February | 19.5mm | 4 | 5.3°C | 10/10 |
| March | 52.9mm | 6 | 12.4°C | 10/10 |
| April | 62.1mm | 6 | 17.3°C | 10/10 |
| May Wet | 128.7mm | 10 | 22.2°C | 9/10 |
| June Wet | 193.2mm | 13 | 26.3°C | 9/10 |
| July Wet | 274.8mm | 18 | 28.7°C | 8/10 |
| August Wet | 401.9mm | 20 | 28.4°C | 8/10 |
| September Wet | 195.8mm | 10 | 25.0°C | 9/10 |
| October | 74.9mm | 7 | 18.2°C | 10/10 |
| November | 72.3mm | 7 | 11.5°C | 10/10 |
| December | 26.6mm | 4 | 2.7°C | 8/10 |
Should you visit Seoul during rainy season?
It can still work. Rain in the wet season often falls in short, intense bursts rather than all-day washouts, prices are lower and crowds thinner. But expect high humidity, disrupted boat trips and island transfers, and the occasional flooded street — August in particular is best avoided.
Best time to avoid the rain
The driest, most comfortable window is All year — see the full best time to visit Seoul guide for the month-by-month breakdown.
Frequently Asked Questions
When is rainy season in Seoul?
Rainy season in Seoul runs May to September, peaking in August with 401.9mm of rain.
What is the wettest month in Seoul?
August — averaging 401.9mm of rain over roughly 20 rainy days.
Can you visit Seoul during rainy season?
It can still work. Rain in the wet season often falls in short, intense bursts rather than all-day washouts, prices are lower and crowds thinner. But expect high humidity, disrupted boat trips and island transfers, and the occasional flooded street — August in particular is best avoided.
When is the dry season in Seoul?
The driest, most comfortable months are All year — see the best time to visit Seoul guide.
Travelling in the wet season anyway?
Pack right for it — the full checklist is on our sister site.
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Check your Seoul packing list at 247PackingList for a full wet-season checklist. For country facts, see our South Korea guide at 247CountryInfo.
Wet season essentials for Seoul
Compact travel umbrella
Windproof, fits in a daypack, dries fast — non-negotiable in monsoon season.
Check Price →Packable waterproof jacket
Light enough for the humidity, sealed enough for the downpours.
Check Price →Dry bag
Keeps phones, passports and cameras dry through boat trips and sudden storms.
Check Price →More wet-season travel gear
Quick-dry travel clothing
Lightweight and quick-drying — ideal for high-humidity wet seasons.
Check Price →Last updated:
Climate data sourced from Open-Meteo (open source, open data licence). Monthly averages calculated from 2020–2023 historical data. Weather can be unpredictable — always check a live forecast before travelling.