ClimateForecastNovemberDecember >>

Osan Climate by Month

Osan experiences great temperature shifts. The city's weather can transition from very warm days to cold weather. It is also known for its large amounts of rain/snowfall. Now, let’s explore all the climate details to give you a full picture.

Average day and night temperature

The climate in Osan is known for significant temperature differences throughout the year, making the weather dynamic. Typically, daytime temperatures range from a very warm 31°C in August to a chilly 4°C in the coolest month, January. Nights are cooler, with temperatures generally dropping to -6°C, particularly during the colder months.

The mean minimum and maximum temperatures throughout the year

Precipitation and rainy days

Osan has a notably wet climate with abundant precipitation, recording 1187 mm of rain/snowfall per year. The climate in Osan shows significant variation throughout the year. Expect heavy rainfall in July, with an average of 281 mm of precipitation over 16 rainy days. In contrast, January offers drier and sunnier days, with around 24 mm of snow/rainfall over 8 snowy/rainy days.

The mean monthly precipitation over the year, including rain, hail and snow

Sunshine over the year

Osan offers a pleasant mix of sunny and slightly overcast days. The difference in sunshine hours between May (8.3 hours daily) and December (5.3 hours daily) provides a bit of variety for visitors and residents.

Monthly hours of sunshine

Data from: Cheonan, South Korea (38 KM, 23 Miles).

Daily hours of sunshine

Data from: Cheonan, South Korea (38 KM, 23 Miles).

The best time of year to visit Osan in South Korea

During the months of May and October you are most likely to experience good weather with pleasant average temperatures that fall between 20°C and 26°C.

Other facts from our historical weather data:
  • Which months have the greatest rainfall in Osan?
    Most rainfall (rainy season) is seen in July and August.
  • Which is the warmest month in Osan?
    August has an average maximum temperature of 31°C and is the warmest month of the year.
  • Which is the coldest month in Osan?
    The coldest month is January with an average maximum temperature of 4°C.
  • Which is the wettest month in Osan?
    July tops the wettest month list with 281 mm of rainfall.
  • Which is the driest month in Osan?
    January is the driest month with 24 mm of precipitation.
  • Which is the sunniest month in Osan?
    May is the sunniest month with an average of 248 hours of sunshine.

  • No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.

    Forecast for Osan

    Thu   Nov 21
    15°C | 5°C
    W 14 km/h
    0.6 mm
    partly cloudy and  chance of slight rain

    partly cloudy and chance of slight rain

    Fri   Nov 22
    10°C | 1°C
    NW 14 km/h
    clear and no rain

    clear and no rain

    Sat   Nov 23
    12°C | -2°C
    NE 4 km/h
    clear and no rain

    clear and no rain