Osan Rainfall & Precipitation: Monthly Averages and Year-Round Insights

This page shows the average amount of rainfall per month in Osan. The numbers are calculated over a 30-year period to provide a reliable average. Now, let’s break down all the details for a clearer picture.

Osan experiences significant rain/snowfall throughout the year, averaging 1187 mm of precipitation annually.

Monthly Precipitation Levels

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

The climate in Osan shows significant variation throughout the year. Expect 281 mm of precipitation during the wettest month July, distributed over 16 rainy days.

In contrast, January offers drier and sunnier days, with around 24 mm of snow/rainfall over 8 snowy/rainy days.

July, the wettest month, has a maximum daytime temperature of 30°C. The city receives 187 hours of sunshine in this period. During the driest month January you can expect a temperature of 4°C. For more detailed insights into the city’s temperatures, visit our Osan Temperature page.

Annual Precipitation in South Korea

The map below shows the annual precipitation across South Korea. You can also select the different months in case you are interested in a specific month.

Amsterdam Precipitation Compared World Wide

Osan’s average annual precipitation is 1187 mm. Let’s compare this to some popular worldwide tourist destinations:

In Barcelona, Spain, the average annual precipitation is 644 mm, evenly distributed across the year with no extreme wet or dry seasons.

In Seoul, South Korea, the average annual precipitation is 1237 mm, with most rain falling during the summer monsoon season.

Perth, Australia, receives 565 mm of rainfall annually, mostly during the winter months.

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

How is Precipitation Measured?

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.

Interesting weather facts

• "Ginger" was the longest-lasting Atlantic tropical storm, which spun around the open ocean for 28 days in 1971.
• The world's largest snowflake was recorded in the Guinness Book of Records, at 38 cm wide and 20 cm thick. The snowflake fell at Fort Keogh, Montana, USA, on 28 January 1887.
• The greatest snowfall recorded was on Mt. Rainier, Washington State, USA—over 31.5 meters fell during the winter of 1972.

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