Tsushima in Summer
In summer (June, July and August), Tsushima sees average daytime highs around 24°C and overnight lows near 23°C, with 605 mm of rain over about 34 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Over the season highs climb from about 20°C in early June to 26°C by late August. The sky is clear or mostly clear about 29% of the time across summer, and the air most often feels oppressive.
Summer is Tsushima's 2nd-best season to visit on our travel score. For the whole year in context, see Tsushima's year-round climate.
- Avg daytime high
- 24°C
- warmest season of the year
- Avg overnight low
- 23°C
- Rainfall
- 605 mm
- 34 wet days
- Avg wind
- 22 km/h
- Travel score
- 6.3
- 2nd-best season
- Months
- Jun · Jul · Aug
Temperature in Tsushima in Summer
Over the season highs climb from about 20°C in early June to 26°C by late August.
A typical summer day in Tsushima reaches about 24°C and drops to 23°C overnight. The warmest of the three months is August, the coolest June.
Tsushima weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 9° / 6° | 65 | 8.6 | 0.8 | 10 | 1.9 |
| Feb | 10° / 7° | 65 | 8.4 | 0.4 | 10.7 | 2.2 |
| Mar | 12° / 10° | 113 | 9.8 | 0.1 | 11.7 | 3.3 |
| Apr | 15° / 13° | 124 | 9.3 | 0 | 12.8 | 4.7 |
| May | 18° / 17° | 129 | 8.3 | 0 | 13.8 | 6.1 |
| Jun | 21° / 20° | 202 | 10.8 | 0 | 14.2 | 6.2 |
| Jul | 25° / 24° | 215 | 11.8 | 0 | 14.1 | 6.4 |
| Aug | 27° / 26° | 189 | 11.7 | 0 | 13.3 | 6.3 |
| Sep | 25° / 23° | 171 | 10.6 | 0 | 12.2 | 6.8 |
| Oct | 21° / 19° | 91 | 6.9 | 0 | 11.1 | 7.1 |
| Nov | 16° / 14° | 82 | 8.3 | 0 | 10.2 | 5.5 |
| Dec | 12° / 9° | 63 | 8.5 | 0.3 | 9.8 | 3.2 |
Cloud cover in Summer
The sky is clear or mostly clear about 29% of the time across summer.
Chance of precipitation in Summer
Tsushima gets around 605 mm of rain over 34 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 22 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 06 min in early June to 12 h 48 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 5.4 kWh/m².
Hazard calendar for Tsushima
In summer, Tsushima overlaps 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.
Is summer a good time to visit Tsushima?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a reasonable time to visit Tsushima for sightseeing.
What to pack for Tsushima in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Tsushima sees daytime highs around 24°C and nights near 23°C. Pack light clothes. Worth having: rain gear, sun protection and a windbreaker. About 34 days see rain.
Sea temperature near Tsushima in Summer
The nearest coast averages about 24°C across summer — 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 16 | 15 | 15 | 16 | 18 | 21 | 25 | 27 | 26 | 24 | 21 | 19 |
| Comfort | Cool | Bracing | Bracing | Cool | Cool | Refreshing | Warm | Warm | Warm | Refreshing | Refreshing | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 16 | Cool |
| Feb | 15 | Bracing |
| Mar | 15 | Bracing |
| Apr | 16 | Cool |
| May | 18 | Cool |
| Jun | 21 | Refreshing |
| Jul | 25 | Warm |
| Aug | 27 | Warm |
| Sep | 26 | Warm |
| Oct | 24 | Refreshing |
| Nov | 21 | Refreshing |
| Dec | 19 | Cool |
UV index in Tsushima in Summer
Clear-sky midday UV across summer averages 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 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 3 | 4 | 6 | 7 | 8 | 8 | 8 | 9 | 9 | 6 | 4 | 2 |
| Level | Moderate | Moderate | High | Very high | Very high | Very high | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 4 | Moderate |
| Mar | 6 | High |
| Apr | 7 | Very high |
| May | 8 | Very high |
| Jun | 8 | Very high |
| Jul | 8 | Very high |
| Aug | 9 | Very high |
| Sep | 9 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 2 | Moderate |
Air quality in Tsushima in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 23 | 27 | 35 | 37 | 35 | 27 | 20 | 19 | 17 | 17 | 21 | 19 |
| Level | Moderate | Moderate | Poor | Poor | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 23 | Moderate |
| Feb | 27 | Moderate |
| Mar | 35 | Poor |
| Apr | 37 | Poor |
| May | 35 | Poor |
| Jun | 27 | Moderate |
| Jul | 20 | Moderate |
| Aug | 19 | Moderate |
| Sep | 17 | Moderate |
| Oct | 17 | Moderate |
| Nov | 21 | Moderate |
| Dec | 19 | Moderate |
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.
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
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.