Seoul weather in January

In January, Seoul sees average daytime highs of 2°C and overnight lows near -7°C, with 20 mm of precipitation across 3.6 wet days and about 9.7 hours of daylight. It is the 12th-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 2°C through the month. The sky is clear or mostly clear about 49% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 24 min at the start of January to 10 h 06 min by month's end. Set against the rest of the year, January is Seoul's 4th-clearest and 4th-windiest month. For the whole year in context, see Seoul's year-round climate.

Daytime high
12th warmest
Overnight low
-7°
1st coldest
Precipitation
20 mm
3.6 wet days
Daylight
9 h 42 min
7:51 AM – 5:32 PM
Cloud cover
46%
4th clearest
Wind
9 km/h
4th windiest
Solar energy
2.72 kWh/m²
Travel score
0.0
out of 10

Seoul is capital and largest city of South Korea.

Air quality
Elevated
PM2.5 21 µg/m³ · 2020
Density
17,099/km²
people per km²
Founded
1395

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 2°C through the month.

A typical January day in Seoul reaches about 2°C in the afternoon and slips back to -7°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between -3°C and 7°C. Set against its neighbours, January runs about 2°C cooler than December and about 3°C cooler than February.

-15°-10°-5°10°151015202531
Avg high (°C)Avg low (°C)
12-6
22-6
32-7
42-7
52-7
62-7
72-7
82-7
92-7
102-7
112-7
122-7
132-7
142-7
152-7
162-7
172-7
182-7
192-7
202-7
212-7
222-7
232-7
242-7
252-7
262-7
272-7
282-7
293-7
303-6
313-6

How January really feels in Seoul

Once humidity and wind are folded in, January averages 0 days that feel above 32°C and 31 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
31
31 feel bitter (≤ -10°C)

The story in January is cold — wind chill drags the overnight "feels like" below the raw low.

Seoul weather by month

How January compares with the rest of the year at a glance. January is the 12th-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -7°203.62.29.70.0
Feb / -5°2541.810.60.3
Mar11° / 386.2111.72.9
Apr18° / 707.3012.96.0
May23° / 12°967.70147.2
Jun27° / 18°1268.8014.56.6
Jul28° / 22°31416.5014.34.8
Aug29° / 22°25815.2013.44.8
Sep26° / 17°1247.6012.37.1
Oct20° / 555.30117.1
Nov12° / 477.10.4103.3
Dec / -5°234.81.59.50.1

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 49% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 14% of January, with mostly cloudy or overcast conditions the remaining 37%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16535
26436
36436
46436
56436
66337
76337
86238
96238
106139
116139
126139
136040
146040
156040
166040
176139
186139
196139
206139
216238
226238
236337
246337
256436
266436
276535
286535
296535
306634
316535

Chance of precipitation in January

Any precipitationSnow

Seoul gets around 20 mm of rain and snow over 3.6 wet days in January, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 11% and peaks near 13% on the wettest days, and about 2 days bring snow.

0%10%20%30%151015202531
Rain chance (%)Snow chance (%)
1138
2128
3128
4128
5127
6117
7117
8116
9106
10106
11106
12106
13106
14106
15106
16117
17117
18117
19117
20127
21128
22128
23128
24128
25128
26128
27128
28128
29127
30127
31127

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

Most of January feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, January lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in January

Winds average 9 km/h in January.

Across January, daily wind ranges from about 9 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
249calm
259calm
269calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 24 min at the start of January to 10 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over January. Sunrise moves from 7:52 AM to 7:44 AM, and sunset from 5:19 PM to 5:47 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.47:525:19
29.57:525:19
39.57:525:20
49.57:525:21
59.57:525:22
69.57:525:23
79.57:525:23
89.57:525:24
99.57:525:25
109.67:525:26
119.67:525:27
129.67:525:28
139.67:525:29
149.67:525:30
159.77:515:31
169.77:515:32
179.77:515:33
189.77:515:34
199.77:505:35
209.87:505:36
219.87:495:37
229.87:495:38
239.87:495:39
249.97:485:40
259.97:475:41
269.97:475:42
279.97:465:43
2810.07:465:44
2910.07:455:45
3010.07:445:46
3110.17:445:47

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.72 kWh/m².

For context, solar energy here swings from a low near 2.35 kWh/m² to a high of 5.79 kWh/m² in May across the year — January's 2.72 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
12.5Moderate
22.5Moderate
32.5Moderate
42.5Moderate
52.5Moderate
62.5Moderate
72.5Moderate
82.5Moderate
92.6Moderate
102.6Moderate
112.6Moderate
122.6Moderate
132.6Moderate
142.6Moderate
152.7Moderate
162.7Moderate
172.7Moderate
182.7Moderate
192.8Moderate
202.8Moderate
212.8Moderate
222.9Moderate
232.9Moderate
242.9Moderate
253.0Moderate
263.0Moderate
273.0Moderate
283.0Moderate
293.1Moderate
303.1Moderate
313.1Moderate
Planning a trip in January

Hazard calendar for Seoul

In seasonPeak

In January, Seoul sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Seoul sits in the Pacific typhoon belt; the season peaks July–October.

Seoul's rainy season runs July–August, when most of the year's rain falls.

Pacific typhoon
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is January a good time to visit Seoul?

Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.0
Sightseeing
12th-best month of the year
0.0
Beach & pool
10th-best month of the year

January is a weaker month for outdoor sightseeing in Seoul.

What to pack for Seoul in January

From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In January, Seoul sees daytime highs around 2°C and nights near -7°C. Pack a warm layer and a heavy coat. About 4 days see rain.

a warm layera heavy coat

Sea temperature near Seoul in January

The nearest coast averages about 6°C in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 38 km away) is warmest in August at about 24°C and coldest in February near 4°C.

It's comfortable for a long swim from Jul 11 to Oct 13 — about 3.1 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan6Bracing
Feb4Bracing
Mar5Bracing
Apr8Bracing
May12Bracing
Jun17Cool
Jul21Refreshing
Aug24Refreshing
Sep23Refreshing
Oct20Cool
Nov15Bracing
Dec10Bracing

UV index in Seoul in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Seoul peaks around July 22 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJul 22UV 8Dec 23UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May5High
Jun7High
Jul8Very high
Aug8Very high
Sep7High
Oct5Moderate
Nov3Moderate
Dec2Low

Air quality in Seoul in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.

Air quality in Seoul is worst in March — around 27 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (August, 14 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Seoul's WHO annual average of 21 µg/m³.

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1327 µg/m³Aug 1214 µg/m³
PM2.5 (µg/m³)Level
Jan25Moderate
Feb25Moderate
Mar27Moderate
Apr22Moderate
May19Moderate
Jun17Moderate
Jul15Moderate
Aug14Moderate
Sep19Moderate
Oct23Moderate
Nov24Moderate
Dec23Moderate
Location & terrain

Where is Seoul?

Seoul sits at 37.6°N, 127.0°E, 38 m above sea level, in South Korea. The nearest listed city is Gwangmyeong, 14 km away.

Topography around Seoul

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Seoul.

Within 3 km, the terrain around Seoul has significant variations in elevation — a maximum elevation change of 302 m around an average of 71 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 777 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,443 m.

The land around Seoul is covered by artificial surfaces (69%) and trees (30%) within 3 km, artificial surfaces (51%) and trees (40%) within 16 km, and trees (48%) within 80 km.

3 km
302 m
16 km
777 m
80 km
1,443 m
treesgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Gwangmyeong 14 km · Siheungdong 14 km · Guri-si 15 km · Goyang-si 16 km · Bucheon-si 19 km · Anyang-si 20 km · Seongnam-si 20 km · Hanam 20 km

South Korea travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / F
220 V · 60 Hz
Prices
≈ 57% of US
price level, 2025
GDP per capita
$36,227
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.5
per 100k, 2023
Road deaths
8.6
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 522
Religion
none 60%Protestant 17%Buddhist 16%Catholic 6%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Seoul (37.566°, 126.9784°, elevation 38 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).