Gwangju weather in September

In September, Gwangju sees average daytime highs of 26°C and overnight lows near 17°C, with 138 mm of rain across 9.5 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 24°C by the end. The sky is clear or mostly clear about 31% of the time in September, and the air most often feels humid.

Daylight stretches from about 12 h 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Gwangju's 7th-clearest and 12th-windiest month. For the whole year in context, see Gwangju's year-round climate.

Daytime high
26°
4th warmest
Overnight low
17°
9th coldest
Rainfall
138 mm
9.5 wet days
Daylight
12 h 12 min
6:20 AM – 6:33 PM
Cloud cover
59%
7th clearest
Wind
7 km/h
12th windiest
Solar energy
4.28 kWh/m²
Travel score
6.6
out of 10

Gwangju is metropolitan city in South Korea.

Air quality
Elevated
PM2.5 18 µg/m³ · 2020
Density
2,796/km²
people per km²
Founded
1986

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 24°C by the end.

A typical September day in Gwangju reaches about 26°C in the afternoon and slips back to 17°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 22°C and 30°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12820
22820
32819
42819
52819
62819
72719
82718
92718
102718
112718
122718
132717
142717
152617
162617
172616
182616
192616
202616
212515
222515
232515
242515
252514
262514
272414
282414
292413
302413

How September really feels in Gwangju

Once humidity and wind are folded in, September 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

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

Gwangju weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -4°295.23.19.90.0
Feb / -2°355.21.310.71.1
Mar13° / 637.60.911.73.7
Apr19° / 887.8012.96.3
May24° / 12°998.2013.87.1
Jun27° / 17°16410.4014.36.1
Jul29° / 22°25517.1014.14.4
Aug30° / 22°22615.5013.34.4
Sep26° / 17°1389.5012.26.6
Oct21° / 575011.17.4
Nov14° / 466.20.210.24.5
Dec / -2°305.11.89.71.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 53%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14060
24159
34159
44258
54357
64357
74456
84456
94555
104555
114654
124753
134852
144852
154951
164951
175050
185149
195149
205149
215149
225149
235149
245149
255050
265050
275149
285149
295050
305149

Chance of precipitation in September

Any precipitation

Gwangju gets around 138 mm of rain over 9.5 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 32% and peaks near 44% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
144
243
342
441
540
640
739
838
937
1036
1135
1235
1334
1433
1532
1631
1730
1829
1928
2027
2126
2226
2325
2425
2525
2625
2724
2824
2923
3023

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 27% of days. Sticky, muggy-or-worse air turns up on roughly 35% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1142537303
2152636293
3162836272
4272936252
5283036232
6293135211
73103235201
84113234181
94133333171
105143332150
116163331140
127183230130
138203229110
1410213127100
151123302690
161325302480
171526292380
181727282170
191829281960
202030271850
212231261640
222432251540
232633251330
242833241230
253034231120
263234221020
27343421920
28373320810
29403319710
30423218710

Wind in September

Winds average 7 km/h in September, the calmest month.

Across September, daily wind ranges from about 7 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 48 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 66 minutes over September. Sunrise moves from 6:09 AM to 6:31 AM, and sunset from 6:55 PM to 6:12 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.86:096:55
212.76:106:54
312.76:106:52
412.76:116:51
512.66:126:50
612.66:136:48
712.66:136:47
812.56:146:45
912.56:156:44
1012.46:166:42
1112.46:166:41
1212.46:176:39
1312.36:186:38
1412.36:196:36
1512.36:196:35
1612.26:206:33
1712.26:216:32
1812.16:226:30
1912.16:226:29
2012.16:236:27
2112.06:246:26
2212.06:256:24
2312.06:266:23
2411.96:266:21
2511.96:276:20
2611.86:286:18
2711.86:296:17
2811.86:296:15
2911.76:306:14
3011.76:316:12

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.28 kWh/m².

For context, solar energy here swings from a low near 2.34 kWh/m² to a high of 5.82 kWh/m² in May across the year — September's 4.28 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.4Bright
24.3Bright
34.3Bright
44.3Bright
54.3Bright
64.3Bright
74.3Bright
84.3Bright
94.3Bright
104.3Bright
114.3Bright
124.3Bright
134.3Bright
144.3Bright
154.3Bright
164.3Bright
174.3Bright
184.3Bright
194.3Bright
204.3Bright
214.2Bright
224.2Bright
234.2Bright
244.2Bright
254.2Bright
264.2Bright
274.2Bright
284.2Bright
294.1Bright
304.1Bright
Planning a trip in September

Hazard calendar for Gwangju

In seasonPeak

In September, Gwangju sits inside its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.

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

Gwangju's rainy season runs June–September, 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 September a good time to visit Gwangju?

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

6.6
Sightseeing
3rd-best month of the year
6.4
Beach & pool
1st-best month of the year

September is a reasonable time to visit Gwangju for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Gwangju in September

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

In September, Gwangju sees daytime highs around 26°C and nights near 17°C. Worth packing: light clothes and rain gear. About 10 days see rain.

light clothesrain gear

Sea temperature near Gwangju in September

The nearest coast averages about 23°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 55 km away) is warmest in August at about 25°C and coldest in February near 6°C.

It's comfortable for a long swim from Jun 26 to Oct 11 — about 3.6 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan8Bracing
Feb6Bracing
Mar7Bracing
Apr10Bracing
May14Bracing
Jun19Cool
Jul23Refreshing
Aug25Warm
Sep23Refreshing
Oct19Cool
Nov15Cool
Dec11Bracing

UV index in Gwangju in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Gwangju peaks around July 12 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 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJul 12UV 8Dec 23UV 2
UV index (midday)Level
Jan2Moderate
Feb3Moderate
Mar6High
Apr7High
May8Very high
Jun8Very high
Jul8Very high
Aug7Very high
Sep8Very high
Oct5High
Nov4Moderate
Dec2Moderate

Air quality in Gwangju in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Gwangju is worst in March — around 27 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (August, 13 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Gwangju's WHO annual average of 18 µg/m³.

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1927 µg/m³Aug 1113 µg/m³
PM2.5 (µg/m³)Level
Jan18Moderate
Feb21Moderate
Mar27Moderate
Apr24Moderate
May20Moderate
Jun17Moderate
Jul13Moderate
Aug13Moderate
Sep15Moderate
Oct16Moderate
Nov17Moderate
Dec15Moderate
Location & terrain

Where is Gwangju?

Gwangju sits at 35.2°N, 126.9°E, 47 m above sea level, in South Korea. The nearest listed city is Masan, 8.0 km away.

Koch'angYeonggwangMuan

Topography around Gwangju

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

Within 3 km, the terrain around Gwangju has significant variations in elevation — a maximum elevation change of 345 m around an average of 69 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,170 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,875 m.

The land around Gwangju is covered by artificial surfaces (78%) and trees (20%) within 3 km, trees (54%), cropland (21%) and artificial surfaces (21%) within 16 km, and trees (52%), cropland (22%) and water (21%) within 80 km.

3 km
345 m
16 km
1,170 m
80 km
1,875 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Masan 8.0 km · Hwasun 12 km · Damyang 19 km · Jangseong 20 km · Naju 23 km · Koch'ang 37 km · Yeonggwang 39 km · Muan 44 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 Gwangju (35.1547°, 126.9156°, elevation 47 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).