October brings 20°C daytime highs, 52mm of precipitation across about 4 wet days and 11 hours of daylight — best for hiking, cycling and reliable sunshine. The strongest run of the year is April to June. August is the quietest month: wetter, but peaceful, and still good for quiet and local.
Long-run climate normals for Seoul. Month ratings compare months within Seoul only — they are not a ranking of Seoul against other destinations, and they are not a forecast for a specific year.
Last updated: · Live forecast data refreshes hourly.
| Best month | October — Hiking, Cycling, Reliable sunshine |
| Best 3-month window | April–June |
| Quietest month | August — Wetter, but peaceful |
| Driest month | January — 21mm |
| Wettest month | July — 395mm |
| Warmest / coolest | July 30°C / February 2°C |
| Seasonality | Strongly seasonal — the months feel like different places |
| Annual rainfall | 1394mm over roughly 108 rain days |
August gets roughly 569% more precipitation than October — 348mm against 52mm. That difference, more than temperature, is what changes how a day here feels.
Seoul swings 28°C between July (30°C) and February (2°C) — the month you pick changes what you pack more than where you go.
June gives you 14.6 hours of daylight against just 9.4 in December — a 5-hour difference in how much you can actually fit into a day.
January is the driest month at 21mm across roughly 2 wet days, while July peaks at 395mm.
January–February sit at or below freezing, so the precipitation shown for those months falls mainly as snow rather than rain — the millimetre figures are water equivalent, not puddles.
May is almost as good as October, but usually quieter and cheaper. If your dates are flexible, it is the easier trip.
Seoul changes character completely through the year — October and August are effectively two different destinations. Pick the month that matches what you want to do, not the highest-rated one.
Ratings compare months within Seoul, not against destinations worldwide: five stars means the best time to be here, not that Seoul beats anywhere else. Tags describe what the conditions actually suit.
| Month | Rating | High / Low | Precipitation | Wet days | Sun | Daylight | Best for |
|---|---|---|---|---|---|---|---|
| January | ★★☆☆☆ | 2°C / -6°C | 21mm (snow) | 2 | 5h | 9.7h | Snow · Skiing · Cabin weekends |
| February | ★★☆☆☆ | 2°C / -6°C | 25mm (snow) | 2 | 5h | 10.6h | Snow · Skiing · Cabin weekends |
| March | ★★★☆☆ | 6°C / -2°C | 46mm (rain/snow) | 3 | 5h | 11.8h | Cabin weekends · Quiet and local |
| April | ★★★★☆ | 12°C / 4°C | 64mm | 5 | 9h | 13h | Reliable sunshine · Spring greenery |
| May | ★★★★★ | 20°C / 12°C | 105mm | 8 | 10h | 14.1h | Hiking · Cycling · Reliable sunshine |
| June | ★★★★☆ | 26°C / 18°C | 133mm | 10 | 7h | 14.6h | Beach days · Swimming |
| July | ★★☆☆☆ | 30°C / 22°C | 395mm | 30 | 5h | 14.3h | Quiet and local |
| August | ★★☆☆☆ | 30°C / 22°C | 348mm | 26 | 5h | 13.4h | Quiet and local |
| September | ★★★☆☆ | 26°C / 18°C | 169mm | 13 | 5h | 12.2h | Beach days · Swimming |
| October | ★★★★★ | 20°C / 12°C | 52mm | 4 | 10h | 11h | Hiking · Cycling · Reliable sunshine |
| November | ★★★★☆ | 12°C / 4°C | 53mm | 4 | 9h | 9.9h | Reliable sunshine · Autumn colour · Low-angle light |
| December | ★★☆☆☆ | 6°C / -2°C | 21mm (rain/snow) | 2 | 5h | 9.4h | Cabin weekends · Festive season · Low-angle light |
| You are planning | Pick | Why |
|---|---|---|
| Sun & beach days | October | 10h daily sunshine, 20°C highs and only 4 rain days. |
| City walking & sightseeing | October | 20°C highs with 11h of daylight — long days without heat fatigue. |
| Photography & light | October | 10h of sun and 11h daylight give the widest window for golden-hour work. |
| Value & fewer crowds | June | Scores 71/100 — close to peak conditions but outside the busiest window. |
| Cooler-weather travel | October | 20°C highs and 12°C nights suit anyone who dislikes heat. |
Each month in Seoul is described from long-run climate normals and then rated relative to the other eleven months in the same city. A five-star January in a cold destination means January is one of the best times to be there — not that it beats a Mediterranean summer.
| Factor | Weight | What it measures |
|---|---|---|
| Temperature | Described | Average daytime high and overnight low for the month, shown as measured rather than judged. |
| Precipitation | Described | Monthly millimetres and wet-day count, labelled as snow or rain/snow where temperatures make that the likely phase. |
| Sunshine & daylight | Described | Average daily sunshine hours and astronomical daylight length at mid-month, from the city’s latitude. |
| “Best for” tags | Derived | Applied only when the conditions genuinely support the activity — snow depth-friendly cold for skiing, 13–24°C and low rain risk for hiking, dark evenings at high latitude for aurora. A month with few strong use cases gets fewer tags rather than padded ones. |
| Star rating | Relative | Ranks the month against the other eleven months in the same city. Never a comparison between cities. |
Figures are long-run climate averages, not a forecast for a specific year. Where a month lacks sourced rainfall or humidity, the value is modelled from temperature range and rain frequency.
October is the best all-round month in Seoul: 20°C highs, 52mm of precipitation and 11 hours of daylight, which suits hiking, cycling and reliable sunshine. The strongest three-month window is April to June.
August — 30°C highs, 348mm of precipitation over roughly 26 days and 13.4 hours of daylight. It is the cheapest and least crowded time to go, and it still works for quiet and local.
January is the driest month at 21mm over about 2 rain days, against 395mm in July. Across the year Seoul records around 1394mm.
Yes, but the months are genuinely different trips. October suits hiking, cycling and reliable sunshine, while August suits quiet and local. Pick the month that matches what you want to do.
Daylight ranges from 9.4 hours in December to 14.6 hours in June, calculated from the city's latitude.