Gyeonggi-do, South Korea · population 158,978 · 156 weather stations within 200 km · records 1760 to 2025
Osan has an average annual daytime high of 16.5°C, based on the 1951 to 1980 baseline. Its warmest month is August, when highs typically reach 29.5°C, and its coldest is January, with overnight lows near -9.1°C.
These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.
Since 1900, Osan's average temperature has risen by +2.4°C. Compared to the earliest station records that begin in 1760, warming totals +2.1°C.
20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.
Daytime highs sit within a comfortable 15°C to 26°C range.
Osan's average annual daytime high is 16.5°C, based on the 1951 to 1980 baseline period. The warmest month is August, with highs averaging 29.5°C, and the coldest is January, with lows averaging -9.1°C.
August is the warmest month in Osan, with typical daytime highs of 29.5°C.
2023 is the hottest year on record for Osan, running +1.9°C above the 1951 to 1980 baseline.
Yes. Since 1900, Osan has warmed by roughly +2.4°C.
April to October typically offers the most comfortable daytime highs, in the 15°C to 26°C range.
Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.