Seoul Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Seoul, Chungcheongbuk-Do, South Korea. The figures are based on a 30-year period (1990–2020) to provide a reliable average. Let's explore the details to provide you with a complete overview.

Seoul has a notably wet climate with abundant precipitation, recording 1236 mm (49 in) of rain/snowfall per year. It does, however, have a distinct dry season during certain months. Have a look at our detailed charts below to see how precipitation varies throughout the year.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

Significant seasonal changes in precipitation occur throughout the year. During the wettest month, July receives substantial rainfall, averaging 316 mm (12 in) of precipitation, recorded across 16 rainy days.

In contrast, the driest month, January brings less snow/rainfall, with 21 mm (0.8 in) over 7 snowy/rainy days.

July, the wettest month, has a maximum daytime temperature of 30°C (86°F). The city receives 124 hours of sunshine in this period. During the driest month January you can expect a temperature of 3°C (37°F). For more detailed insights into the city's temperatures, visit our Seoul Temperature page.

Seoul's average annual precipitation is 1236 mm (49 in). Let's compare this to some popular worldwide tourist destinations:

In Lisbon, Portugal, the average annual precipitation is 774 mm (30 in), characterized by wet winters and dry summers typical of the Mediterranean climate.

In Shanghai, China, the annual average precipitation is 1347 mm (53 in), with a humid subtropical climate.

Perth, Australia, receives 565 mm (22 in) of rainfall annually, mostly during the winter months.

Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm (66 in) of annual rainfall, with the heaviest precipitation occurring during September and October.

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

Tropical Rainforests: In tropical regions, rainfall is generally abundant year-round. Areas near the equator, like the Amazon rainforest, can receive up to 3000 mm (118 in) of rain annually.

Desert Regions: Deserts such as the Sahara and Arabian deserts typically see less than 250 mm (9.8 in) of rainfall annually. Rainfall tends to be infrequent, but when it does occur, it is often intense.

Temperate Zones: In temperate regions, precipitation tends to be more evenly distributed, though areas closer to the ocean may see more rain in the winter months, and areas further inland experience drier summers.

Polar Regions: Precipitation in polar regions, like Antarctica, is extremely low, often falling as snow. Average annual precipitation in Antarctica is less than 200 mm (7.9 in), with some areas receiving as little as 50 mm (2 in) annually.

• Mawsynram in India is noted as being the wettest place on earth, with over 11 meters (36 feet) of rain falling every year.
• In contrast, Antofagasta in Chile is among the driest places on the planet, getting less than 0.1mm (0.004 inches) per year, with some years recording virtually no rainfall.
• Nearly 1,650 thunderstorm cells are estimated over the planet at any given time.

For more detailed information about Seoul's weather, including sunshine hours, humidity levels, and temperature data, visit our Seoul Climate page.