Tsushima weather in September

In September, Tsushima sees average daytime highs of 25°C and overnight lows near 23°C, with 171 mm of rain across 10.6 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 26°C in the first days to 23°C by the end. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels muggy.

Daylight stretches from about 12 h 42 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Tsushima's 7th-clearest and 5th-windiest month. For the whole year in context, see Tsushima's year-round climate.

Daytime high
25°
3rd warmest
Overnight low
23°
10th coldest
Rainfall
171 mm
10.6 wet days
Daylight
12 h 12 min
6:11 AM – 6:23 PM
Cloud cover
57%
7th clearest
Wind
26 km/h
5th windiest
Solar energy
4.37 kWh/m²
Travel score
6.8
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 26°C in the first days to 23°C by the end.

A typical September day in Tsushima reaches about 25°C in the afternoon and slips back to 23°C overnight — a 1°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 26°C. Set against its neighbours, September runs about 2°C cooler than August and about 4°C warmer than October.

15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12625
22625
32625
42625
52625
62624
72624
82624
92524
102524
112524
122524
132524
142524
152523
162523
172523
182423
192423
202423
212423
222423
232422
242422
252422
262322
272322
282322
292322
302321

Tsushima weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 658.60.8101.9
Feb10° / 658.40.410.72.2
Mar12° / 10°1139.80.111.73.3
Apr15° / 13°1249.3012.84.7
May18° / 17°1298.3013.86.1
Jun21° / 20°20210.8014.26.2
Jul25° / 24°21511.8014.16.4
Aug27° / 26°18911.7013.36.3
Sep25° / 23°17110.6012.26.8
Oct21° / 19°916.9011.17.1
Nov16° / 14°828.3010.25.5
Dec12° / 638.50.39.83.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 50%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14852
24951
34852
44852
54852
64951
75050
85050
95050
105149
115149
125149
135149
145050
155149
165050
175050
184951
194951
205050
215050
225050
235050
245050
255149
265149
275149
285248
295347
305347

Chance of precipitation in September

Any precipitation

Tsushima gets around 171 mm of rain over 10.6 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 35% and peaks near 40% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
140
240
340
440
540
639
739
839
939
1039
1138
1238
1337
1436
1536
1635
1734
1834
1933
2032
2132
2232
2331
2431
2530
2630
2729
2829
2928
3028

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 33% of days. Sticky, muggy-or-worse air turns up on roughly 66% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1005323726
2006333724
3017343722
4018353720
5019363718
60210373616
70211373614
80212383512
90313383411
100415383310
11041638329
12151838318
13161937297
14172037287
15182236266
16292335256
172112435235
182122534225
193132733204
203142833194
214152932173
224163031163
235173030153
246183129132
257193228122
267213227112
279223226101
2810233225101
291124322391
301225322281

Wind in September

Winds average 26 km/h in September.

Across September, daily wind ranges from about 25 km/h on the calmest days to 27 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202530
Wind speed (km/h)Feels
125breezy
225breezy
325breezy
425breezy
525breezy
625breezy
725breezy
825breezy
925breezy
1025breezy
1125breezy
1226breezy
1326breezy
1426breezy
1526breezy
1626breezy
1726breezy
1826breezy
1926breezy
2026breezy
2126breezy
2227breezy
2327breezy
2427breezy
2527breezy
2626breezy
2726breezy
2826breezy
2926breezy
3026breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 42 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 60 minutes over September. Sunrise moves from 6:00 AM to 6:21 AM, and sunset from 6:45 PM to 6:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.76:006:45
212.76:016:44
312.76:026:42
412.66:026:41
512.66:036:39
612.66:046:38
712.56:046:37
812.56:056:35
912.56:066:34
1012.46:076:32
1112.46:076:31
1212.46:086:29
1312.36:096:28
1412.36:096:26
1512.26:106:25
1612.26:116:23
1712.26:126:22
1812.16:126:21
1912.16:136:19
2012.16:146:18
2112.06:146:16
2212.06:156:15
2312.06:166:13
2411.96:176:12
2511.96:176:10
2611.86:186:09
2711.86:196:07
2811.86:206:06
2911.76:206:05
3011.76:216:03

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.37 kWh/m².

For context, solar energy here swings from a low near 2.41 kWh/m² to a high of 5.87 kWh/m² in May across the year — September's 4.37 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.8Bright
24.7Bright
34.7Bright
44.7Bright
54.6Bright
64.6Bright
74.6Bright
84.6Bright
94.5Bright
104.5Bright
114.5Bright
124.5Bright
134.5Bright
144.4Bright
154.4Bright
164.4Bright
174.4Bright
184.3Bright
194.3Bright
204.3Bright
214.3Bright
224.3Bright
234.2Bright
244.2Bright
254.2Bright
264.2Bright
274.1Bright
284.1Bright
294.1Bright
304.1Bright
Planning a trip in September

Hazard calendar for Tsushima

In seasonPeak

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

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

Tsushima's rainy season runs March–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 Tsushima?

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

6.8
Sightseeing
2nd-best month of the year
5.9
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Tsushima for sightseeing.

What to pack for Tsushima in September

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

In September, Tsushima sees daytime highs around 25°C and nights near 23°C. Worth packing: light clothes, rain gear and a windbreaker. About 11 days see rain.

light clothesrain geara windbreaker

Sea temperature near Tsushima in September

The nearest coast averages about 26°C in September — 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 27°C and coldest in March near 15°C.

It's comfortable for a long swim from Jun 6 to Nov 28 — about 5.8 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Bracing
Mar15Bracing
Apr16Cool
May18Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Refreshing
Nov21Refreshing
Dec19Cool

UV index in Tsushima in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Tsushima peaks around August 24 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 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 highHighModerateAug 24UV 9Dec 22UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr7Very high
May8Very high
Jun8Very high
Jul8Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Tsushima 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 Tsushima is worst in April — around 37 µg/m³ PM2.5 (poor), about 2.2× the cleanest month (September, 17 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateApr 1637 µg/m³Sep 2117 µg/m³
PM2.5 (µg/m³)Level
Jan23Moderate
Feb27Moderate
Mar35Poor
Apr37Poor
May35Poor
Jun27Moderate
Jul20Moderate
Aug19Moderate
Sep17Moderate
Oct17Moderate
Nov21Moderate
Dec19Moderate
Location & terrain

Where is Tsushima?

Tsushima sits at 34.2°N, 129.3°E, 6 m above sea level, in Japan. The nearest listed city is Iki, 62 km away.

Topography around Tsushima

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

Within 3 km, the terrain around Tsushima has significant variations in elevation — a maximum elevation change of 554 m around an average of 116 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 640 m; within 80 km, large variations in elevation — a maximum elevation change of 628 m.

The land around Tsushima is covered by trees (60%) and water (33%) within 3 km, water (67%) and trees (31%) within 16 km, and water (95%) within 80 km.

3 km
554 m
16 km
640 m
80 km
628 m
treesgrasslandartificial surfaceswater
September weather nearby: Iki 62 km · Geoje 86 km · Hirado 96 km · Kyosai 96 km · Sinhyeon 97 km · Busan 102 km · Matsuura 103 km · Karatsu 106 km

Japan travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
100 V · 50 / 60 Hz
Prices
≈ 65% of US
price level, 2025
GDP per capita
$35,951
2025
Happiness
6.1 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.2
per 100k, 2023
Road deaths
3.6
per 100k/yr, 2019
Income group
High
World Bank
English
Very low
EF EPI 446
Religion
Shintoism 49%Buddhism 46%other 4%Christianity 1%

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 Tsushima (34.2063°, 129.2908°, elevation 6 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).