Incheon weather in May

In May, Incheon sees average daytime highs of 21°C and overnight lows near 13°C, with 92 mm of rain across 7.5 wet days and about 14 hours of daylight. It is the 5th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 19°C in the first days to 23°C by the end. The sky is clear or mostly clear about 40% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 30 min at the start of May to 14 h 24 min by month's end. Set against the rest of the year, May is Incheon's 8th-clearest and 7th-windiest month. For the whole year in context, see Incheon's year-round climate.

Daytime high
21°
5th warmest
Overnight low
13°
8th coldest
Rainfall
92 mm
7.5 wet days
Daylight
14 hours
5:29 AM – 7:30 PM
Cloud cover
52%
8th clearest
Wind
11 km/h
7th windiest
Solar energy
5.82 kWh/m²
Travel score
6.9
out of 10
Air quality
Elevated
PM2.5 19 µg/m³ · 2020

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 19°C in the first days to 23°C by the end.

A typical May day in Incheon reaches about 21°C in the afternoon and slips back to 13°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 24°C. Set against its neighbours, May runs about 5°C warmer than April and about 4°C cooler than June.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
11910
21911
31911
41911
51911
62011
72012
82012
92012
102012
112012
122012
132012
142013
152113
162113
172113
182113
192113
202114
212214
222214
232214
242214
252214
262215
272215
282315
292315
302315
312316

How May really feels in Incheon

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 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
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Incheon weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -6°193.629.70.0
Feb / -4°243.81.410.60.2
Mar10° / 365.50.811.72.4
Apr16° / 657012.95.3
May21° / 13°927.50146.9
Jun25° / 18°1227.8014.57.1
Jul27° / 22°29815.1014.35.5
Aug29° / 23°24413.8013.45.3
Sep25° / 18°1217.6012.37.2
Oct19° / 11°545.30117.1
Nov12° / 487.30.3103.3
Dec / -3°2251.29.50.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 40% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 14% of May, with mostly cloudy or overcast conditions the remaining 45%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15644
25446
35446
45446
55446
65446
75446
85446
95347
105347
115446
125446
135446
145446
155545
165446
175446
185545
195644
205644
215644
225644
235644
245644
255644
265545
275545
285545
295446
305446
315347

Chance of precipitation in May

Any precipitation

Incheon gets around 92 mm of rain over 7.5 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 24% and peaks near 27% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)
126
226
326
426
526
626
726
827
927
1027
1127
1226
1326
1426
1526
1625
1725
1825
1925
2024
2124
2223
2323
2422
2521
2621
2720
2820
2919
3019
3119

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 61% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
1871210
2861310
3851410
4841510
5821710
6811810
7801910
8792010
9782110
10772210
11762310
12732520
13722620
14702820
15692920
16663130
17633340
18603550
19583660
20553870
21533980
224941100
234642120
244343140
254044160
263645181
273346201
283046231
292845261
302545291
312244332

Wind in May

Winds average 11 km/h in May.

Across May, daily wind ranges from about 10 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
112calm
212calm
312calm
412calm
512calm
612calm
712calm
812calm
911calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 30 min at the start of May to 14 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 54 minutes over May. Sunrise moves from 5:45 AM to 5:20 AM, and sunset from 7:16 PM to 7:42 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.55:457:16
213.65:437:17
313.65:427:18
413.65:417:19
513.75:407:20
613.75:397:21
713.75:387:22
813.85:377:23
913.85:367:23
1013.85:357:24
1113.95:347:25
1213.95:337:26
1313.95:327:27
1413.95:317:28
1514.05:307:29
1614.05:297:30
1714.05:287:30
1814.15:287:31
1914.15:277:32
2014.15:267:33
2114.15:257:34
2214.25:257:35
2314.25:247:36
2414.25:237:36
2514.25:237:37
2614.35:227:38
2714.35:227:39
2814.35:217:39
2914.35:207:40
3014.35:207:41
3114.45:207:42

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.82 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.33 kWh/m² to a high of 5.82 kWh/m² in May across the year — May's 5.82 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.6Bright
25.6Bright
35.6Bright
45.6Bright
55.6Bright
65.6Bright
75.6Bright
85.6Bright
95.7Bright
105.7Bright
115.7Bright
125.7Bright
135.7Bright
145.7Bright
155.7Bright
165.8Bright
175.8Bright
185.8Bright
195.8Bright
205.9Bright
215.9Bright
225.9Bright
235.9Bright
246.0Bright
256.0Bright
266.0Intense
276.0Intense
286.0Intense
296.0Intense
306.0Intense
316.0Intense
Planning a trip in May

Hazard calendar for Incheon

In seasonPeak

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

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

Incheon'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 May a good time to visit Incheon?

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

6.9
Sightseeing
4th-best month of the year
4.1
Beach & pool
5th-best month of the year

May is a reasonable time to visit Incheon for sightseeing.

What to pack for Incheon in May

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

In May, Incheon sees daytime highs around 21°C and nights near 13°C. Worth packing: sun protection. About 8 days see rain.

sun protection

Sea temperature near Incheon in May

The nearest coast averages about 12°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore 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 Incheon in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Incheon 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 Incheon in May

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Incheon is worst in March — around 25 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (August, 12 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Incheon's WHO annual average of 19 µg/m³.

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1324 µg/m³Aug 1213 µg/m³
PM2.5 (µg/m³)Level
Jan22Moderate
Feb23Moderate
Mar25Moderate
Apr20Moderate
May17Moderate
Jun15Moderate
Jul14Moderate
Aug12Moderate
Sep17Moderate
Oct20Moderate
Nov22Moderate
Dec21Moderate
Location & terrain

Where is Incheon?

Incheon sits at 37.5°N, 126.7°E, 43 m above sea level, in South Korea. The nearest listed city is Bucheon-si, 8.0 km away.

Topography around Incheon

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

Within 3 km, the terrain around Incheon has only modest variations in elevation — a maximum elevation change of 187 m around an average of 35 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 389 m; within 80 km, large variations in elevation — a maximum elevation change of 1,126 m.

The land around Incheon is covered by artificial surfaces (71%) and trees (23%) within 3 km, artificial surfaces (42%), trees (20%) and water (20%) within 16 km, and trees (35%) and water (31%) within 80 km.

3 km
187 m
16 km
389 m
80 km
1,126 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Bucheon-si 8.0 km · Gwangmyeong 14 km · Ansan 18 km · Siheungdong 18 km · Gimpo-si 19 km · Anyang-si 21 km · Gunpo 24 km · Uiwang 24 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 Incheon (37.4565°, 126.7052°, elevation 43 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).