Ansan weather in January

In January, Ansan sees average daytime highs of 2°C and overnight lows near -3°C, with 23 mm of precipitation across 4.1 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 37% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 30 min at the start of January to 10 h 06 min by month's end. Set against the rest of the year, January is Ansan's 9th-clearest and 2nd-windiest month. For the whole year in context, see Ansan's year-round climate.

Daytime high
12th warmest
Overnight low
-3°
1st coldest
Precipitation
23 mm
4.1 wet days
Daylight
9 h 42 min
7:51 AM – 5:33 PM
Cloud cover
54%
9th clearest
Wind
16 km/h
2nd windiest
Solar energy
2.57 kWh/m²
Travel score
0.0
out of 10

Ansan is city in South Korea.

Density
4,172/km²
people per km²
Founded
1986

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 Ansan reaches about 2°C in the afternoon and slips back to -3°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between -3°C and 6°C. Set against its neighbours, January runs about 3°C cooler than December and about 1°C cooler than February.

-10°-5°10°151015202531
Avg high (°C)Avg low (°C)
13-2
23-2
33-2
42-2
52-2
62-2
72-2
82-3
92-3
102-3
112-3
122-3
132-3
142-3
152-3
162-3
172-3
182-3
192-3
202-3
212-3
222-3
232-3
242-3
252-3
262-3
272-3
282-3
292-3
302-3
312-3

How January really feels in Ansan

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
wind chill below the day's low

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

Ansan 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 / -3°234.12.59.70.0
Feb / -1°304.31.310.60.0
Mar / 426.10.911.71.1
Apr12° / 797.3012.93.6
May17° / 13°1047.70145.9
Jun22° / 18°1277.6014.56.8
Jul25° / 22°29814.4014.36.0
Aug27° / 23°23912.8013.46.2
Sep24° / 19°1277.3012.37.3
Oct18° / 13°625.60116.7
Nov11° / 578.20.3103.1
Dec / -0°285.81.89.50.2

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 15% of January, with mostly cloudy or overcast conditions the remaining 48%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15545
25446
35446
45347
55347
65149
75149
85149
95050
105050
114951
124951
135050
145050
155050
165050
175050
185050
195050
205149
215149
225248
235347
245347
255446
265545
275545
285644
295842
305842
315842

Chance of precipitation in January

Any precipitationSnow

Ansan gets around 23 mm of rain and snow over 4.1 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 13% and peaks near 16% on the wettest days, and about 3 days bring snow.

0%10%20%30%151015202531
Rain chance (%)Snow chance (%)
1168
2158
3158
4148
5148
6147
7137
8137
9137
10127
11127
12128
13128
14128
15128
16129
17139
18139
19139
20149
21149
22149
23149
24148
25148
26138
27137
28137
29137
30136
31126

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 16 km/h in January.

Across January, daily wind ranges from about 16 km/h on the calmest days to 16 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
116light breeze
216light breeze
316light breeze
416light breeze
516light breeze
616light breeze
716light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1316light breeze
1416light breeze
1516light breeze
1616light breeze
1716light breeze
1816light breeze
1916light breeze
2016light breeze
2116light breeze
2216light breeze
2316light breeze
2416light breeze
2516light breeze
2616light breeze
2716light breeze
2816light breeze
2916light breeze
3016light breeze
3116light breeze

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 30 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 36 minutes over January. Sunrise moves from 7:52 AM to 7:44 AM, and sunset from 5:20 PM to 5:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.57:525:20
29.57:525:21
39.57:525:21
49.57:525:22
59.57:525:23
69.57:525:24
79.57:525:25
89.67:525:25
99.67:525:26
109.67:525:27
119.67:525:28
129.67:525:29
139.67:525:30
149.77:525:31
159.77:515:32
169.77:515:33
179.77:515:34
189.77:515:35
199.87:505:36
209.87:505:37
219.87:495:38
229.87:495:39
239.97:495:40
249.97:485:41
259.97:485:42
269.97:475:43
2710.07:465:44
2810.07:465:45
2910.07:455:46
3010.07:445:47
3110.17:445:48

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.57 kWh/m².

For context, solar energy here swings from a low near 2.24 kWh/m² to a high of 5.83 kWh/m² in May across the year — January's 2.57 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
12.3Moderate
22.3Moderate
32.3Moderate
42.4Moderate
52.4Moderate
62.4Moderate
72.4Moderate
82.4Moderate
92.4Moderate
102.4Moderate
112.4Moderate
122.5Moderate
132.5Moderate
142.5Moderate
152.5Moderate
162.5Moderate
172.6Moderate
182.6Moderate
192.6Moderate
202.6Moderate
212.7Moderate
222.7Moderate
232.8Moderate
242.8Moderate
252.8Moderate
262.9Moderate
272.9Moderate
282.9Moderate
293.0Moderate
303.0Moderate
313.0Moderate
Planning a trip in January

Hazard calendar for Ansan

In seasonPeak

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

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

Ansan'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 Ansan?

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

0.0
Sightseeing
11th-best month of the year
0.0
Beach & pool
9th-best month of the year

January is a weaker month for outdoor sightseeing in Ansan.

What to pack for Ansan in January

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

In January, Ansan sees daytime highs around 2°C and nights near -3°C. Pack a warm layer and a heavy coat. About 4 days see rain.

a warm layera heavy coat

Sea temperature near Ansan 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 18 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 Ansan 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 Ansan peaks around July 23 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 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 23UV 8Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May6High
Jun7High
Jul8Very high
Aug8Very high
Sep7High
Oct5Moderate
Nov3Moderate
Dec2Low

Air quality in Ansan 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 Ansan is worst in March — around 160 µg/m³ PM2.5 (very unhealthy), about 2.0× the cleanest month (August, 81 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0306090120150180JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyVery unhealthyUnhealthyMar 13158 µg/m³Aug 1282 µg/m³
PM2.5 (µg/m³)Level
Jan145Unhealthy
Feb149Unhealthy
Mar160Very unhealthy
Apr127Unhealthy
May111Unhealthy
Jun98Unhealthy
Jul88Unhealthy
Aug81Unhealthy
Sep110Unhealthy
Oct132Unhealthy
Nov142Unhealthy
Dec133Unhealthy
Location & terrain

Where is Ansan?

Ansan sits at 37.3°N, 126.8°E, 15 m above sea level, in South Korea. The nearest listed city is Anyang-si, 12 km away.

Topography around Ansan

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

Within 3 km, the terrain around Ansan has only modest variations in elevation — a maximum elevation change of 198 m around an average of 24 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 470 m; within 80 km, large variations in elevation — a maximum elevation change of 1,126 m.

The land around Ansan is covered by artificial surfaces (58%) and trees (33%) within 3 km, trees (36%) and artificial surfaces (32%) within 16 km, and trees (39%) and water (27%) within 80 km.

3 km
198 m
16 km
470 m
80 km
1,126 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
January weather nearby: Anyang-si 12 km · Uiwang 12 km · Gunpo 12 km · Hwaseong-si 13 km · Siheungdong 16 km · Suwon 17 km · Gwangmyeong 18 km · Incheon 18 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 Ansan (37.3236°, 126.8219°, elevation 15 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).