Masan weather in September

In September, Masan sees average daytime highs of 26°C and overnight lows near 17°C, with 145 mm of rain across 9.8 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 33% of the time in September, and the air most often feels muggy.

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 Masan's 6th-clearest and 12th-windiest month. For the whole year in context, see Masan's year-round climate.

Daytime high
26°
4th warmest
Overnight low
17°
9th coldest
Rainfall
145 mm
9.8 wet days
Daylight
12 h 12 min
6:20 AM – 6:34 PM
Cloud cover
57%
6th clearest
Wind
8 km/h
12th windiest
Solar energy
4.4 kWh/m²
Travel score
6.6
out of 10

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 Masan reaches about 26°C in the afternoon and slips back to 17°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 29°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.

10°15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12820
22820
32820
42820
52820
62820
72719
82719
92719
102719
112719
122718
132718
142718
152618
162617
172617
182617
192617
202617
212516
222516
232516
242516
252515
262515
272415
282415
292414
302414

How September really feels in Masan

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.

Masan 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 / -3°275.33.19.90.0
Feb / -2°345.31.410.71.0
Mar12° / 607.30.811.73.6
Apr18° / 867.6012.96.3
May23° / 12°978013.87.2
Jun27° / 18°16210.1014.36.3
Jul29° / 22°24316.2014.14.6
Aug30° / 23°22415.7013.34.3
Sep26° / 17°1459.8012.26.6
Oct21° / 11°554.5011.17.5
Nov14° / 466.30.210.24.6
Dec / -1°295.42.29.71.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% 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 50%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14357
24258
34357
44357
54555
64555
74654
84654
94555
104654
114753
124852
134852
144951
155050
165050
175149
185149
195248
205347
215347
225446
235446
245446
255446
265446
275446
285446
295545
305644

Chance of precipitation in September

Any precipitation

Masan gets around 145 mm of rain over 9.8 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 33% and peaks near 46% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
146
245
344
443
542
641
740
840
939
1038
1137
1236
1335
1434
1533
1632
1731
1830
1929
2028
2127
2226
2326
2425
2525
2624
2724
2823
2923
3022

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the muggy band about 27% of days. Sticky, muggy-or-worse air turns up on roughly 40% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1032040324
2142240303
3142440283
4152540262
5162640252
6272740231
7282839211
83102838201
93112938181
104132937160
115152936150
125162935140
136182934130
148202932110
159222830100
161024282990
171126282780
181327272570
191429272360
201631262160
211732262050
221933261840
232134251640
242335241530
252535241330
262735231220
272935221120
283235211020
29353520910
30373419810

Wind in September

Winds average 8 km/h in September, the calmest month.

Across September, daily wind ranges from about 8 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

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 6:56 PM to 6:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.86:096:56
212.76:106:54
312.76:116:53
412.76:116:51
512.66:126:50
612.66:136:48
712.66:146:47
812.56:146:45
912.56:156:44
1012.46:166:43
1112.46:176:41
1212.46:176:40
1312.36:186:38
1412.36:196:37
1512.36:206:35
1612.26:206:34
1712.26:216:32
1812.16:226:31
1912.16:236:29
2012.16:246:27
2112.06:246:26
2212.06:256:24
2312.06:266:23
2411.96:276:22
2511.96:276:20
2611.86:286:19
2711.86:296:17
2811.86:306:16
2911.76:316:14
3011.76:316:13

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.4 kWh/m².

For context, solar energy here swings from a low near 2.27 kWh/m² to a high of 5.91 kWh/m² in May across the year — September's 4.4 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.5Bright
44.5Bright
54.5Bright
64.5Bright
74.5Bright
84.5Bright
94.5Bright
104.4Bright
114.4Bright
124.4Bright
134.4Bright
144.4Bright
154.4Bright
164.4Bright
174.4Bright
184.4Bright
194.4Bright
204.3Bright
214.3Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.3Bright
274.2Bright
284.2Bright
294.2Bright
304.2Bright
Planning a trip in September

Hazard calendar for Masan

In seasonPeak

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

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

Masan'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 Masan?

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 Masan for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Masan in September

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

In September, Masan 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 Masan 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 50 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 Masan 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 Masan 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 Masan 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 Masan is worst in March — around 61 µg/m³ PM2.5 (unhealthy), about 2.1× the cleanest month (August, 28 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecPoorUnhealthyPoorModeratePoorModerateMar 1960 µg/m³Aug 1129 µg/m³
PM2.5 (µg/m³)Level
Jan41Poor
Feb48Poor
Mar61Unhealthy
Apr54Poor
May45Poor
Jun39Poor
Jul29Moderate
Aug28Moderate
Sep33Moderate
Oct35Moderate
Nov38Poor
Dec34Moderate
Location & terrain

Where is Masan?

Masan sits at 35.1°N, 126.8°E, 18 m above sea level, in South Korea. The nearest listed city is Gwangju, 8.0 km away.

MuanKoch'ang

Topography around Masan

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

Within 3 km, the terrain around Masan has only modest variations in elevation — a maximum elevation change of 190 m around an average of 30 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,162 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,717 m.

The land around Masan is covered by artificial surfaces (35%), cropland (31%) and trees (23%) within 3 km, trees (47%), cropland (25%) and artificial surfaces (22%) within 16 km, and trees (48%), water (25%) and cropland (22%) within 80 km.

3 km
190 m
16 km
1,162 m
80 km
1,717 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Gwangju 8.0 km · Naju 15 km · Hwasun 16 km · Jangseong 19 km · Damyang 25 km · Yeonggwang 34 km · Muan 36 km · Koch'ang 36 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 Masan (35.1272°, 126.8315°, elevation 18 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).