In December, Osan typically sees daytime highs of 3.4°C and overnight lows around -6.0°C. Compared to the annual average high of 16.5°C, December runs -13.1°C.
December in Osan averages a daytime high of 3.4°C and an overnight low of -6.0°C.
December runs -13.1°C compared to Osan's annual average high of 16.5°C, ranking #11 of 12 months by warmth.
Plan for daytime highs near 3.4°C and cooler evenings around -6.0°C.