Seoul, the capital of South Korea, sits in the northwest of the country on the Han River, ringed by mountains and not far from the Yellow Sea coast, at approximately 37.57°N, 126.98°E. It has a monsoon-influenced climate on the boundary between humid continental and humid subtropical (Köppen Dwa/Cwa) with four sharply distinct seasons: hot, humid, rainy summers and cold, dry winters, driven by the East Asian monsoon.

Summer, from June to August, is hot, humid and by far the rainiest season, with August the hottest month — average highs around 29–31°C — and high humidity that makes it feel sweltering. The heart of the rains is the changma or monsoon front of late June and July, followed by intense heat; July alone can bring over 400 mm of rain. Late summer into September is also typhoon season, when storms occasionally reach the peninsula with heavy rain and wind.

Winter, from December to February, is cold, dry and often bitter, with January the coldest month — average highs around 2°C and lows well below freezing, and cold snaps driven by the Siberian High that can plunge temperatures toward -15 to -20°C. The influence of that continental high makes Seoul far colder than its latitude alone would suggest. Snow falls on around 25 days a year, though usually lightly, and the season is dry and often crisply sunny.

Seoul receives around 1,240–1,450 mm of precipitation a year, overwhelmingly concentrated in the summer — roughly two-thirds falls between June and September, with July the wettest month — while winter is very dry. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

Seoul's winters are shaped by a distinctive three-cold-four-warm rhythm as the Siberian High waxes and wanes, alternating bitter spells with milder ones. Spring brings another hazard: the yellow dust (hwangsa) blown in from the deserts of Mongolia and China, which can haze the sky and irritate the lungs. Spring and autumn, with their clear blue skies and comfortable temperatures, are widely considered the finest seasons.

To follow any single measurement in Seoul more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.