Korea Weather by Month: Seasons and Temperature Guide
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Quick answer
Korea features four distinct seasons with annual average temperatures between 7°C and 15°C. January is the coldest month, with Seoul overnight averages dropping to -5.5°C, while August is the hottest, reaching around 30°C. Spring (April to May) and autumn (September to October) provide clear, mild conditions ideal for traveling on foot.
At a glance
- Hottest month nationwide
- August (Seoul average high: 30.0°C; Gwangju: 30.9°C)
- Source, 2023-03-30(opens in a new tab)
What should you expect during spring from March to May?
Spring brings clear, mild weather across the Korean peninsula, making it one of the most comfortable periods for walking tours and outdoor sightseeing.
- March: Seoul averages a daytime high of 11.0°C and a night low of 1.9°C, while southern cities like Busan reach 13.8°C. Southern cherry blossoms begin opening toward late March (around March 25 in Jeju and Busan, and March 28 in Jeonju and Gyeongju).
- April: Seoul warms significantly, averaging a high of 17.9°C and a low of 8.0°C. Cherry blossoms generally open in Seoul around April 3 and peak roughly one week later, near April 10.
- May: Conditions turn pleasantly warm. Seoul averages a high of 23.6°C and a low of 13.5°C, while Gwangju reaches 24.8°C. Late spring shifts attention to colorful seasonal blooms like azaleas and roses.
How hot and humid is summer from June to August?
Korean summers are characterized by hot, humid weather, making coastal beaches and water activities the primary seasonal highlights.
- June: Temperatures climb steadily, with Seoul averaging a daily high of 27.6°C and a low of 18.7°C.
- July: High humidity sets in alongside hot temperatures. Seoul averages a high of 29.0°C and a low of 22.3°C, while Gwangju regularly reaches 30.0°C.
- August: August is the hottest month of the year nationwide. Seoul averages daytime highs of 30.0°C with humid overnight lows of 22.9°C. Gwangju records average highs of 30.9°C, and Busan reaches 29.5°C with muggy nights averaging 23.7°C.
Light, breathable fabrics and sun protection are essential when traveling during these months.
When does autumn weather arrive from September to November?
Autumn provides crisp, clear days with moderate temperatures, making it a favorite season for hiking and city exploration.
- September: Early autumn remains comfortably warm, with Seoul averaging a high of 26.2°C and a low of 17.7°C, while Busan reaches 26.4°C.
- October: Cool, refreshing air settles in. Seoul averages a daytime high of 20.2°C and an overnight low of 10.6°C. First fall foliage appears on northern peaks like Seoraksan around October 3 before spreading south to Bukhansan, Jirisan, and Hallasan later in the month.
- November: Temperatures drop noticeably as winter approaches. Seoul averages a high of 11.9°C and a low of 3.5°C. Peak foliage concludes during early to mid-November across central and southern national parks, including Bukhansan (November 4), Naejangsan (November 11), and Hallasan (November 13).
How cold does winter get from December to February?
Winter across Korea is officially characterized as cold and arid. While southern coastal areas remain relatively mild, central and northern regions experience freezing conditions.
- December: Seoul averages a daytime high of 4.2°C and drops to an overnight low of -3.4°C. Winter illumination festivals launch across the country, including the Garden of Morning Calm Lighting Festival and Daegu's E-World Illumination.
- January: January is the coldest month of the year. Seoul averages a daily high of only 2.1°C and an overnight low of -5.5°C. In contrast, southern Busan stays milder with an average low of -0.1°C.
- February: The cold persists, with Seoul averaging a high of 5.1°C and a low of -3.2°C.
Popular activities include winter light festivals, snow trekking, and coastal New Year sunrise gatherings.
What weather mistakes should travelers avoid in Korea?
Visitors often plan around nationwide weather averages without factoring in regional progression and seasonal extremes:
- Assuming uniform bloom and foliage dates: Cherry blossoms travel south to north, opening in Jeju and Busan over a week before Seoul. Conversely, autumn foliage travels north to south, peaking in northern mountains like Seoraksan weeks before southern parks like Naejangsan.
- Underestimating summer humidity: July and August are not merely hot; high humidity makes outdoor walking strenuous during midday hours.
- Expecting mild winters in central cities: While Busan rarely drops far below freezing, Seoul regularly experiences sub-zero overnight temperatures requiring insulated outerwear and wind protection.
- Relying on outdoor festival schedules without verification: Major winter sunrise and lighting events can adjust operating hours or cancel due to adverse weather conditions.
Questions people ask
What are the best months to visit Korea for outdoor sightseeing?
Spring (March through May) and autumn (September through November) offer the most pleasant conditions for outdoor exploration. Both seasons feature clear, mild weather, avoiding the heavy humidity of midsummer and the sub-zero chill of midwinter.
Which month is the hottest in Korea?
August is the hottest month across the country. Daytime high temperatures average 30.0°C in Seoul, 29.5°C in Busan, and 30.9°C in Gwangju, accompanied by warm, humid overnight lows above 22°C.
Which month is the coldest in Korea?
January is the coldest month of the year. Seoul experiences average monthly lows of -5.5°C and highs of 2.1°C, while Gwangju drops to -2.7°C. Southern coastal cities such as Busan are comparatively milder, averaging around -0.1°C.
When do cherry blossoms bloom in Korea?
Cherry blossoms typically start opening in southern regions like Jeju and Busan around March 25, reaching Seoul around April 3. Peak bloom usually occurs approximately seven days after initial flowering, creating full blooms in Seoul by roughly April 10.
When does autumn foliage begin in Korea?
Autumn foliage starts in early October, beginning at northern peaks such as Seoraksan Mountain on October 3. Color spreads south toward Bukhansan, Jirisan, and Hallasan later in October, with peak foliage arriving between late October and mid-November across various national parks.