Korea weather in December: how cold it gets, what Koreans wear (Updated Nov 11, 2026)

The flight to Seoul in December is booked, and now the next question shows up: how cold does it actually get, and what do you pack if you have never dealt with sub-zero mornings?

In Seoul in December, mornings average −3.4°C and afternoons only reach 4.2°C. Koreans handle it by wearing four layers, then peeling the outer ones off the moment they step into a heated building.

We are a team of Koreans living and working in Seoul. The numbers in this article come straight from the climate normals and official outlook of the Korea Meteorological Administration (KMA).

Korea temperatures in December: official numbers by city

Short answer: Seoul and Incheon are below freezing in the morning, Busan and Jeju rarely are. The figures below are KMA climate normals, the 30-year average for 1991–2020.

Daily low to highMean0°C (freezing)

Seoul 서울

low −3.4° · mean 0.2° · high 4.2°

Snow days 6.4 · rain or snow days 7.8

Incheon 인천

low −2.7° · mean 0.7° · high 4.5°

Snow days 6.6 · rain or snow days 7.7

Busan 부산

low 2.0° · mean 5.8° · high 10.4°

Snow days 0.9 · rain or snow days 4.7

Jeju 제주

low 5.6° · mean 8.3° · high 11.0°

Snow days 5.3 · rain or snow days 11.5

−6°−3°0°3°6°9°12°

Look at the black 0°C line. The bars for Seoul and Incheon start to the left of it, meaning the average morning is below freezing.

We included Incheon because the main airport is there. Step out of the terminal early in the morning or at night and it is already as cold as Seoul.

One thing people miss: Jeju is mild but windy. The average December wind speed in Jeju City is 4.1 m/s, almost double Seoul’s 2.3 m/s, with only 79 hours of sunshine for the month against 163 in Seoul. So Jeju feels colder than the numbers suggest.

The December 2026 outlook: probably warmer than normal

KMA expects December 2026 to run warmer than normal. In the 3-month outlook published on Oct 23, 2026, the chance of a warmer month is 50%, near normal 40%, colder 10%.

The reason is a strong El Niño. According to KMA, sea surface temperatures in the El Niño monitoring zone hit a record high for September in 2026, and the peak is expected in December.

December precipitation is forecast as near or above normal (40% each). With temperatures hovering around zero, that can mean rain and wet snow on the same day.

When does it snow in Korea?

In Seoul, snow starts in November, picks up in December and peaks in January. According to the KMA normals, Seoul averages 2.3 snow days in November, 6.4 days in December and 7.1 days in January.

Read that number carefully. A “snow day” counts even when only a few flakes fall. A proper white blanket like the photo below does not happen every week.

Busan gets almost no snow in December (0.9 days). If seeing snow is the main goal, Seoul or the northern cities make more sense than Busan.

What do Koreans wear in December?

Koreans do not rely on one giant coat. The approach is several thin layers, then covering the head, neck and hands. That is also what the Korea Disease Control and Prevention Agency (KDCA) recommends for cold weather.

Outdoors, Seoul in December

−3.4° to 4.2°C

Inside Korean homes

about 22–25°C

1. 1

   발열내의 · 내복

   bal-yeol-nae-ui · nae-bok

   Thermal underwear (top + leggings)

   KDCA: thermal underwear alone adds about 2.4°C of warmth

   Stays on
2. 2

   니트 · 맨투맨

   ni-teu · maen-tu-maen

   Knit sweater or sweatshirt

   Go thin so it layers

   Stays on
3. 3

   패딩 · 롱패딩

   pae-ding · rong-pae-ding

   Padded or down jacket, knee-length is the local favorite

   Light and a little roomy

   Comes off indoors
4. 4

   목도리 · 장갑 · 모자 · 핫팩

   mok-do-ri · jang-gap · mo-ja · haet-paek

   Scarf, gloves, hat, hand warmers

   Head, neck and hands get cold first

   Comes off indoors

Layers 1 and 2 stay on all day. Layers 3 and 4 are the ones you take off and put back on every time you enter or leave a building.

According to KDCA, thermal underwear alone adds about 2.4°C of warmth. KDCA also recommends a light, slightly roomy coat and covering the head and neck with a hat, scarf and mask.

On gloves, KDCA says mittens (벙어리장갑, beong-eo-ri-jang-gap) are warmer than five-finger gloves. If you use your phone a lot while walking, pick a pair with touchscreen fingertips.

When there is a cold wave alert (한파)

If the news or a phone alert shows 한파주의보 (han-pa-ju-ui-bo), that is a cold wave advisory. Under the KMA criteria republished by the Seoul city government, one trigger is a forecast morning low of −12°C or below for 2 days or more.

The higher level is 한파경보 (han-pa-gyeong-bo), a cold wave warning, issued when the forecast morning low is −15°C or below for 2 days. An alert can also be issued when the morning temperature drops suddenly by 10°C or more from the day before, down to 3°C or lower.

On days like that, KDCA recommends checking the “feels like” temperature (체감온도, che-gam-on-do) before heading out, cutting outdoor time and avoiding icy roads and stairs. For a visitor, that means swapping the long walk for a museum, an underground mall or a cafe.

Korean words you will see in winter

Summary

• Seoul in December: mornings −3.4°C, afternoons 4.2°C, about 6 snow days (KMA normals 1991–2020).
• Busan and Jeju stay above freezing, but Jeju is windy and often overcast.
• December 2026 has a 50% chance of being warmer than normal. Still pack for sub-zero mornings.
• Dress in 4 layers like Koreans do, and keep the coat and scarf easy to take off in heated rooms.

Bring at least one thick coat and long thermal underwear from home for day one, and if you are still unsure what to pack for your city, ask in the comments or on the forum.