Ōarai in Summer
In summer (June, July and August), Ōarai sees average daytime highs around 25°C and overnight lows near 21°C, with 432 mm of rain over about 41 wet days across the season. It is the warmest season of the year and the 2nd-wettest season.
Over the season highs climb from about 21°C in early June to 27°C by late August. The sky is clear or mostly clear about 17% of the time across summer, and the air most often feels oppressive.
Summer is Ōarai's best season of the year to visit on our travel score. For the whole year in context, see Ōarai's year-round climate.
- Avg daytime high
- 25°C
- warmest season of the year
- Avg overnight low
- 21°C
- Rainfall
- 432 mm
- 41 wet days
- Avg wind
- 12 km/h
- Travel score
- 5.8
- best season of the year
- Months
- Jun · Jul · Aug
Temperature in Ōarai in Summer
Over the season highs climb from about 21°C in early June to 27°C by late August.
A typical summer day in Ōarai reaches about 25°C and drops to 21°C overnight. The warmest of the three months is August, the coolest June.
How summer really feels in Ōarai
Once humidity and wind are folded in, summer brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
summer sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Ōarai 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 | 8° / 3° | 73 | 7.6 | 1.3 | 9.8 | 1.7 |
| Feb | 9° / 3° | 71 | 8.1 | 1.6 | 10.6 | 1.8 |
| Mar | 12° / 6° | 126 | 13 | 0.9 | 11.7 | 2.9 |
| Apr | 16° / 10° | 124 | 12.4 | 0.1 | 12.9 | 4.7 |
| May | 20° / 15° | 148 | 12.6 | 0 | 13.9 | 5.8 |
| Jun | 23° / 18° | 159 | 14.1 | 0 | 14.4 | 5.7 |
| Jul | 26° / 22° | 162 | 14.9 | 0 | 14.2 | 5.7 |
| Aug | 28° / 23° | 111 | 12.1 | 0 | 13.4 | 6.0 |
| Sep | 25° / 21° | 176 | 14.1 | 0 | 12.2 | 6.0 |
| Oct | 20° / 16° | 213 | 13.5 | 0 | 11.1 | 5.8 |
| Nov | 16° / 11° | 106 | 10.5 | 0 | 10.1 | 4.8 |
| Dec | 11° / 6° | 71 | 8.6 | 0.2 | 9.6 | 2.9 |
Cloud cover in Summer
The sky is clear or mostly clear about 17% of the time across summer.
Chance of precipitation in Summer
Ōarai gets around 432 mm of rain over 41 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 12 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 14 h 18 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 4.9 kWh/m².
Hazard calendar for Ōarai
In summer, Ōarai overlaps its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Ōarai sits in the Pacific typhoon belt; the season peaks July–October.
Is summer a good time to visit Ōarai?
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 Ōarai for sightseeing.
What to pack for Ōarai in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Ōarai sees daytime highs around 25°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 41 days see rain.
Sea temperature near Ōarai in Summer
The nearest coast averages about 22°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 24°C and coldest in February near 13°C.
It's comfortable for a long swim from Jun 24 to Oct 28 — about 4.2 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 15 | 13 | 13 | 15 | 17 | 19 | 22 | 24 | 23 | 21 | 19 | 16 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Cool | Cool | Refreshing | Warm | Refreshing | Refreshing | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 15 | Bracing |
| Feb | 13 | Bracing |
| Mar | 13 | Bracing |
| Apr | 15 | Bracing |
| May | 17 | Cool |
| Jun | 19 | Cool |
| Jul | 22 | Refreshing |
| Aug | 24 | Warm |
| Sep | 23 | Refreshing |
| Oct | 21 | Refreshing |
| Nov | 19 | Cool |
| Dec | 16 | Cool |
UV index in Ōarai in Summer
Clear-sky midday UV across summer averages 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 Ōarai peaks around July 24 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 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) | 2 | 4 | 4 | 6 | 8 | 9 | 10 | 10 | 8 | 6 | 3 | 2 |
| Level | Moderate | Moderate | Moderate | High | Very high | Very high | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Moderate |
| Feb | 4 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 10 | Very high |
| Aug | 10 | Very high |
| Sep | 8 | Very high |
| Oct | 6 | High |
| Nov | 3 | Moderate |
| Dec | 2 | Moderate |
Air quality in Ōarai 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 Ōarai is worst in March — around 25 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (December, 14 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) | 15 | 18 | 25 | 25 | 24 | 19 | 16 | 15 | 15 | 16 | 16 | 14 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 18 | Moderate |
| Mar | 25 | Moderate |
| Apr | 25 | Moderate |
| May | 24 | Moderate |
| Jun | 19 | Moderate |
| Jul | 16 | Moderate |
| Aug | 15 | Moderate |
| Sep | 15 | Moderate |
| Oct | 16 | Moderate |
| Nov | 16 | Moderate |
| Dec | 14 | Moderate |
Where is Ōarai?
Ōarai sits at 36.3°N, 140.6°E, 22 m above sea level, in Japan. The nearest listed city is Katsuta, 9.0 km away.
Topography around Ōarai
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Ōarai.
Within 3 km, the terrain around Ōarai has only modest variations in elevation — a maximum elevation change of 45 m around an average of 6 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 64 m; within 80 km, large variations in elevation — a maximum elevation change of 1,005 m.
The land around Ōarai is covered by water (56%) within 3 km, water (50%) within 16 km, and trees (36%), water (29%) and cropland (20%) 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 Ōarai (36.3141°, 140.5839°, elevation 22 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.