Korea Weather by Month: Best Time to Visit

The best time to visit Korea for comfortable weather is May or October. Both months are mild and mostly dry, and the light is good for walking all day. July and August are hot, humid and wet. January is properly cold in Seoul and drier than any other month. Every temperature, rainfall and storm figure below comes from the Korea Meteorological Administration’s (KMA) official 1991–2020 climate normals. Those are 30-year averages, so they tell you what’s typical, not what next week will bring. This guide is part of our Practical Tips section.

The temperature tables use KMA’s three main stations for visitors: Seoul (stand-in for the capital region), Busan (south-east coast) and Jeju City (north side of Jeju Island). Rain is total monthly precipitation in millimetres. In winter that includes snow, measured as water.

The short version

• Spring (April–May): Seoul highs rise from 17.9°C in April to 23.6°C in May. Rain stays modest until June. May is the safest pick for good weather nationwide.
• Summer (June–August): August is the hottest month in all three cities, with highs of 29.5–30.1°C. July is the wettest month in Seoul and Busan. The monsoon (jangma) normally fills late June to late July, and typhoons are possible from July.
• Autumn (September–November): September is still warm and fairly wet, and Jeju gets 228 mm that month. October is dry and mild everywhere (Seoul 20.2°C high, 52 mm). By late November Seoul is close to freezing at night.
• Winter (December–February): Seoul averages lows of −3 to −6°C. Jeju stays above freezing, and Busan’s January lows sit right at freezing (−0.1°C). Jeju is mild but grey. Precipitation is low everywhere except Jeju.

Korea weather by month: Seoul, Busan and Jeju

Two patterns stand out. First, Seoul’s rain is concentrated in summer. KMA counts 892.1 mm in June–August, about 63% of the year’s 1,417.9 mm, and only 67.6 mm in December–February. Second, the south is not always wetter. Busan gets more rain than Seoul from March to June, while Seoul gets more in July and August.

Month by month

January and February

Seoul is at its coldest: January averages 2.1°C by day and −5.5°C at night (about 36°F and 22°F). February is only slightly milder. Days are dry and often sunny: Seoul logs about 170 hours of sunshine in January, but wind makes it feel colder than the thermometer says. Busan is noticeably milder, with an 8.2°C high and a low just under freezing. Jeju City stays above freezing on average, but it’s the cloudiest place in this guide. It gets 70 hours of January sunshine against Busan’s 203.

Plan around: Seollal, the Lunar New Year. In 2027 the official holiday runs 6–9 February (Saturday to Tuesday, with 9 February a substitute holiday because 7 February is a Sunday). See the holiday section below.

March

Winter loosens its grip in March. Seoul climbs to an 11.0°C high but still averages 1.9°C at night, so bring a warm layer. Precipitation stays low in Seoul (36.9 mm), but Busan and Jeju already get about 90 mm.

April

Seoul averages 17.9°C by day and 8.0°C at night, with 72.9 mm of rain. Spring flowers bloom across the country in this period, but the exact cherry-blossom week moves with each year’s temperatures, so check the forecasts published in March rather than fixing dates months ahead. Spring can also bring yellow-dust and fine-dust days, so check the daily air-quality forecast if you’re sensitive to it.

May

May is the most reliable month for good weather. Seoul averages 23.6°C by day and 13.5°C at night (about 74°F and 56°F), with low humidity (60%). Busan and Jeju are within a degree or two of Seoul. Rain rises to about 96–156 mm, still well under half of July’s total in Seoul and Busan. The one catch is that May has several public holidays. In 2027 these are 1 May (Labour Day, with 3 May as the substitute day), 5 May (Children’s Day) and 13 May (Buddha’s Birthday), so domestic travel is busy around those dates.

June

June warms up quickly: Seoul averages 27.6°C, with humidity rising to 66%. The monsoon normally starts in the last third of the month: 19 June on Jeju, 23 June in the south and 25 June in the central region. Early June is often still pleasant. By the end of the month, plan for rain.

July

July is the wettest month in Seoul (414.4 mm) and Busan (326.8 mm). During the monsoon window, KMA’s normals show about 17–18 rain days and roughly 340–380 mm of rain per region. It doesn’t rain all day every day, though. Fronts move north and south, and heavy bursts alternate with dry spells. The monsoon normally ends around 20 July on Jeju, 24 July in the south and 26 July in the central region. Humidity peaks at 76% in Seoul. Typhoons become possible this month (1.0 affecting Korea on average).

August

August is the hottest month in all three cities: Seoul averages 30.0°C by day and 22.9°C at night, and nights stay warm and sticky. It’s also the peak typhoon month, with 1.2 typhoons affecting Korea on average. Seoul still gets 348.2 mm of rain, even after the monsoon officially ends, mostly from heavy showers.

September

Heat eases through September. Seoul drops to a 26.2°C average high, and evenings are comfortable by the end of the month. September is still wet: Seoul gets 141.5 mm, and Jeju 227.8 mm, its second-wettest month, because typhoons are still around (0.8 affecting Korea on average). Chuseok, the harvest holiday, usually falls in September or early October. In 2027 it’s 14–16 September.

October

October is the driest of the comfortable months and the easiest to recommend: Seoul averages 20.2°C by day and 10.6°C at night (about 68°F and 51°F), with 52.2 mm of rain. Busan (22.5°C) and Jeju (21.6°C) are warmer still. Autumn colour arrives at different times each year, so check the foliage forecasts rather than fixing a date. Two public holidays fall in early October. In 2026, National Foundation Day (3 October) is a Saturday, so Monday 5 October is a substitute holiday. Hangeul Day is Friday 9 October. Both make long weekends, so popular trains fill up.

November

November cools fast in Seoul, from an 11.9°C average high to a 3.5°C low. KMA’s normals put Seoul’s first frost on 28 October, first ice on 3 November and first snow on 20 November. Busan and Jeju are about 4–7°C milder.

December

Seoul is back below freezing at night (−3.4°C) with a 4.2°C high and only 22.6 mm of precipitation. Christmas Day is a public holiday. Jeju City is the mildest of the three (11.0°C high, 5.6°C low) but often overcast, and Busan is close behind by day (10.4°C).

Typhoon season: what the numbers say

On average, only about one in seven Pacific typhoons reaches Korea, and almost all of those arrive between July and September. When one does, flights and ferries can be cancelled, so keep the last day or two of a Jeju trip flexible in August and September. If you’re flying out of Incheon, see how to get from Incheon Airport to Seoul to plan your timing on the way back.

Holidays to plan around (not weather, but just as important)

Weather isn’t the only thing that changes a trip. On the two big family holidays, many Koreans travel to their home towns, some shops and restaurants close, and long-distance trains sell out early.

KTX tickets now open two months ahead, so book holiday-period trains as soon as your dates are fixed. Our KTX booking guide covers how and when. On Seollal and Chuseok themselves, check opening days for individual sights and restaurants before you go.

Which month suits which trip?

Packing by season, briefly

• December–February: a proper winter coat, hat and gloves for Seoul. Busan and Jeju need a lighter coat.
• March–April and November: layers. With day-night swings of about 8–10°C in Seoul, a light jacket for evenings is essential.
• May and October: light layers and one warmer top for evenings.
• June–September: breathable clothes, a compact umbrella and quick-dry shoes. Sort out mobile data before you land so you can check rain radar on the go. Our guide to eSIM vs SIM vs pocket Wi-Fi compares the options.

For getting around once you’re there, see T-money vs WOWPASS vs Climate Card. Transit is the same in every season, but in summer downpours you’ll be glad to be underground.

How to read these numbers

KMA’s 1991–2020 normals are the official 30-year baseline used for forecasts in Korea. They describe a typical year, and any given month can run well above or below them. For the week of your trip, check the KMA forecast (weather.go.kr has an English version) or a weather app about 10 days out. During the monsoon or a typhoon, follow KMA’s weather warnings and your airline’s notices.