Seoul weather in December
December is one of the least pleasant months in Seoul: highs of 3°C (37°F) and about 22 mm (0.9 in) of rain on average. Nights average -5°C (24°F) and cloud cover 55% (NASA POWER, 2001–2025 averages). The sea averages 9°C (47°F). It is the 2nd driest month of the year and the 2nd coolest. Compared with November, it is cooler and drier; January brings highs of 1°C (33°F) and 20 mm (0.8 in) of rain.
Figures are long-term averages for Seoul, the largest city in Seoul. See below for other places.
Is December a good time to visit Seoul?
least pleasant month Weather score 45/100.
December is one of the least pleasant months for weather in Seoul. For better conditions, consider May–Jun, Sep–Oct.
Does it rain a lot in Seoul in December?
No, it is usually dry: about 22 mm (0.9 in) falls in an average December. It is the 2nd driest month of the year.
How warm is Seoul in December?
Days average 3°C (37°F) and nights -5°C (24°F).
Seoul weather by month
| Month | High | Low | Rain | Cloud | Sea | Weather |
|---|---|---|---|---|---|---|
| January | 1°C (33°F) | -7°C (19°F) | 20 mm | 56% | 4°C (39°F) | least pleasant |
| February | 3°C (38°F) | -5°C (23°F) | 31 mm | 52% | 3°C (37°F) | least pleasant |
| March | 9°C (47°F) | -1°C (30°F) | 37 mm | 50% | 6°C (42°F) | fair |
| April | 15°C (59°F) | 5°C (40°F) | 72 mm | 53% | 11°C (52°F) | fair |
| May | 21°C (70°F) | 11°C (51°F) | 84 mm | 56% | 17°C (62°F) | best |
| June | 25°C (78°F) | 16°C (61°F) | 116 mm | 65% | 23°C (74°F) | best |
| July | 27°C (81°F) | 21°C (69°F) | 361 mm | 76% | 28°C (82°F) | least pleasant |
| August | 28°C (83°F) | 22°C (71°F) | 260 mm | 65% | 30°C (87°F) | least pleasant |
| September | 24°C (76°F) | 16°C (62°F) | 138 mm | 57% | 28°C (82°F) | best |
| October | 18°C (65°F) | 10°C (49°F) | 53 mm | 44% | 22°C (71°F) | best |
| November | 11°C (51°F) | 3°C (37°F) | 47 mm | 52% | 16°C (60°F) | fair |
| December | 3°C (37°F) | -5°C (24°F) | 22 mm | 55% | 9°C (47°F) | least pleasant |
Sources: 2001–2025 monthly averages from NASA POWER (MERRA-2 reanalysis), sea temperature from Open-Meteo Marine. Page updated . How we rate months
Weather across Seoul in December
Weather can differ a lot within Seoul: coasts, hills and mountains each have their own climate.
| Place | High | Low | Rain | Weather |
|---|---|---|---|---|
| Seoul | 3°C (37°F) | -5°C (24°F) | 22 mm | least pleasant |
| Siheungdong | 3°C (37°F) | -5°C (24°F) | 22 mm | least pleasant |