🌃 Seoul Weather

Monsoon summers, Siberian winters

Seoul has a humid continental climate with a strong monsoon influence, giving it one of the more extreme seasonal ranges of any major Asian capital. Summers are hot, humid, and dominated by a concentrated rainy season, while winters are cold and dry under the influence of Siberian air sweeping in from the northwest.

The summer monsoon (jangma)

The defining summer event is "jangma," the East Asian monsoon, when a stalled front parks over the peninsula in late June and July and unleashes the bulk of the year's rain — often in intense, flooding downpours. The rest of summer stays hot and humid, with August highs around 86°F (30°C).

Cold, dry winters

Winters are cold and dry, with January highs around 36°F (2°C) and frequent cold snaps. Koreans describe the rhythm as "samhan saon" — three cold days followed by four milder ones — as waves of Siberian air ebb and flow. Spring can bring yellow dust blowing in from the deserts of China and Mongolia.

Seoul averages about 56 inches (1,420 mm) of precipitation a year, more than half of it falling in the summer monsoon. Spring and autumn are dry, sunny, and pleasant — autumn especially, with crisp air and brilliant foliage in the surrounding mountains.

Monsoon summers and Siberian winters

Seoul's climate swings hard with the seasons. The summer monsoon, the 'jangma,' brings a concentrated rainy season in late June and July that dumps much of the year's precipitation, followed by hot, humid August days and the threat of late-summer typhoons sweeping up from the south.

Winters are cold and dry, dominated by Siberian high pressure that delivers a distinctive rhythm of three cold days followed by four milder ones. Spring and autumn are the prized seasons — spring for cherry blossoms, autumn for clear skies and foliage — though spring also carries yellow dust blowing in from the Asian interior.