Asahi in Summer

In summer (June, July and August), Asahi sees average daytime highs around 26°C and overnight lows near 22°C, with 385 mm of rain over about 35 wet days across the season. It is the warmest season of the year and the 3rd-wettest season.

Over the season highs climb from about 22°C in early June to 27°C by late August. The sky is clear or mostly clear about 21% of the time across summer, and the air most often feels oppressive.

Summer is Asahi's best season of the year to visit on our travel score. For the whole year in context, see Asahi's year-round climate.

Avg daytime high
26°C
warmest season of the year
Avg overnight low
22°C
Rainfall
385 mm
35 wet days
Avg wind
16 km/h
Travel score
6.1
best season of the year
Months
Jun · Jul · Aug

Temperature in Asahi in Summer

Average highAverage lowShaded bands: 10–90% of days

Over the season highs climb from about 22°C in early June to 27°C by late August.

A typical summer day in Asahi reaches about 26°C and drops to 22°C overnight. The warmest of the three months is August, the coolest June.

15°20°25°30°35°JunJulAug

Asahi 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.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan10° / 949.39.92.2
Feb10° / 879.610.62.2
Mar12° / 14213.711.73.1
Apr16° / 12°11912.612.94.8
May20° / 16°13411.913.95.9
Jun23° / 20°16512.914.45.9
Jul26° / 23°1331214.26.2
Aug28° / 24°889.913.46.3
Sep25° / 22°17013.112.26.1
Oct21° / 18°22613.911.15.9
Nov17° / 13°12211.810.15.1
Dec12° / 91109.63.4

Cloud cover in Summer

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% of the time across summer.

0%25%50%75%100%JunJulAug

Chance of precipitation in Summer

Any precipitation

Asahi gets around 385 mm of rain over 35 wet days across summer. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%JunJulAug

Humidity in Summer

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%JunJulAug

Wind in Summer

Winds average 16 km/h across summer.

05101520JunJulAug

Sunrise & sunset in Summer

DaylightNight

Daylight runs from about 14 h 12 min in early June to 12 h 48 min by late August. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJunJulAug

Solar energy in Summer

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across summer, about 5.3 kWh/m².

0246JunJulAug
Planning a trip in summer

Hazard calendar for Asahi

In seasonPeak

In summer, Asahi overlaps its pacific typhoon season. The full year is below, with each hazard's peak months called out.

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

Pacific typhoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is summer a good time to visit Asahi?

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.

6.1
Sightseeing
1st-best month of the year
5.7
Beach & pool
1st-best month of the year

summer is a reasonable time to visit Asahi for sightseeing.

What to pack for Asahi in Summer

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

In summer, Asahi sees daytime highs around 26°C and nights near 22°C. Pack light clothes. Worth having: rain gear and sun protection. About 35 days see rain.

light clothesrain gearsun protection

Sea temperature near Asahi in Summer

The nearest coast averages about 23°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 25°C and coldest in February near 15°C.

It's comfortable for a long swim from Jun 5 to Nov 22 — about 5.6 months when the water holds above 20°C.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Bracing
Mar15Cool
Apr16Cool
May19Cool
Jun21Refreshing
Jul23Refreshing
Aug25Warm
Sep25Warm
Oct23Refreshing
Nov21Refreshing
Dec18Cool

UV index in Asahi in Summer

LowModerateHighVery highExtreme

Clear-sky midday UV across summer averages around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Asahi peaks around August 12 at about 10 (extreme) — 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highVery highHighModerateAug 12UV 10Jan 1UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr7High
May8Very high
Jun9Very high
Jul10Very high
Aug10Extreme
Sep8Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Asahi in Summer

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Asahi is worst in April — around 20 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (December, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1920 µg/m³Dec 178 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb11Good
Mar18Moderate
Apr20Moderate
May19Moderate
Jun14Moderate
Jul12Good
Aug11Good
Sep10Good
Oct10Good
Nov9Good
Dec7Good
Location & terrain

Where is Asahi?

Asahi sits at 35.7°N, 140.7°E, 5 m above sea level, in Japan. The nearest listed city is Sōsa, 9.0 km away.

Topography around Asahi

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

Within 3 km, the terrain around Asahi has only modest variations in elevation — a maximum elevation change of 19 m around an average of 7 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 71 m; within 80 km, large variations in elevation — a maximum elevation change of 840 m.

The land around Asahi is covered by cropland (41%) and artificial surfaces (39%) within 3 km, water (34%), cropland (27%) and trees (22%) within 16 km, and water (44%) and trees (24%) within 80 km.

3 km
19 m
16 km
71 m
80 km
840 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Summer weather nearby: Sōsa 9.0 km · Yōkaichiba 9.0 km · Omigawa 15 km · Hasaki 17 km · Choshi 17 km · Yokoshiba 17 km · Kamisu 20 km · Sawara 23 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 Asahi (35.7167°, 140.65°, elevation 5 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.