Innoshima weather in August

In August, Innoshima sees average daytime highs of 30°C and overnight lows near 26°C, with 93 mm of rain across 8.4 wet days and about 13.3 hours of daylight. It is the 1st-warmest and 8th-wettest month of the year here.

Day-to-day highs hold fairly steady near 30°C through the month. The sky is clear or mostly clear about 36% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 13 h 42 min at the start of August to 12 h 48 min by month's end. Set against the rest of the year, August is Innoshima's 4th-clearest and 10th-windiest month. For the whole year in context, see Innoshima's year-round climate.

Daytime high
30°
1st warmest
Overnight low
26°
12th coldest
Rainfall
93 mm
8.4 wet days
Daylight
13 h 18 min
5:33 AM – 6:50 PM
Cloud cover
57%
4th clearest
Wind
10 km/h
10th windiest
Solar energy
5.22 kWh/m²
Travel score
5.3
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 30°C through the month.

A typical August day in Innoshima reaches about 30°C in the afternoon and slips back to 26°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 32°C. Set against its neighbours, August runs about 2°C warmer than July and about 3°C warmer than September.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13026
23026
33026
43026
53026
63026
73026
83026
93026
103026
113026
123026
133026
143026
153026
163026
173026
183026
193026
203026
213026
223026
233026
243026
252926
262925
272925
282925
292925
302925
312925

How August really feels in Innoshima

Once humidity and wind are folded in, August averages 29 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
29
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in August is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Innoshima weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 6311.30.6102.0
Feb10° / 6910.20.710.72.2
Mar13° / 10311.1011.73.5
Apr17° / 12°11210.4012.85.4
May21° / 16°1299.9013.86.5
Jun24° / 20°19212.3014.26.1
Jul28° / 24°17111.2014.15.7
Aug30° / 26°938.4013.35.3
Sep27° / 23°15310.7012.26.3
Oct22° / 18°1278.8011.17.0
Nov17° / 12°678.2010.25.6
Dec12° / 7110.60.29.83.2

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

Beyond those clear spells, partly cloudy skies cover about 15% of August, with mostly cloudy or overcast conditions the remaining 49%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15248
25248
35248
45248
55248
65248
75248
85149
95149
105149
115050
125050
135050
145050
155050
165050
175050
185149
195149
205050
215149
225149
235149
245149
255050
265050
275050
285050
295050
305050
315050

Chance of precipitation in August

Any precipitation

Innoshima gets around 93 mm of rain over 8.4 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 28% and peaks near 34% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%151015202531
Rain chance (%)
126
226
325
425
525
625
725
825
925
1025
1125
1226
1326
1426
1527
1627
1728
1828
1928
2029
2129
2229
2330
2430
2531
2631
2732
2832
2933
3033
3134

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the oppressive band about 58% of days. Sticky, muggy-or-worse air turns up on roughly 97% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
10046036
20045937
30045937
40045937
50045937
60045937
70045937
80145837
90145837
100155737
110155836
120155836
130155836
140165835
151165834
161175833
171285732
181295731
1912105730
2012115729
2112125827
2213135726
2313145824
2414155723
2514165821
2615175720
2715185818
2816205716
2917215615
3017225614
3118245512

Wind in August

Winds average 10 km/h in August.

Across August, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3011calm
3111calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 13 h 42 min at the start of August to 12 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 54 minutes over August. Sunrise moves from 5:21 AM to 5:44 AM, and sunset from 7:05 PM to 6:31 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:217:05
213.75:227:04
313.75:237:03
413.65:247:03
513.65:247:02
613.65:257:01
713.65:267:00
813.55:276:59
913.55:276:58
1013.55:286:57
1113.45:296:56
1213.45:306:55
1313.45:306:53
1413.45:316:52
1513.35:326:51
1613.35:336:50
1713.35:336:49
1813.25:346:48
1913.25:356:47
2013.25:366:45
2113.15:366:44
2213.15:376:43
2313.15:386:42
2413.05:396:40
2513.05:396:39
2613.05:406:38
2712.95:416:36
2812.95:426:35
2912.95:426:34
3012.85:436:32
3112.85:446:31

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.22 kWh/m².

For context, solar energy here swings from a low near 2.29 kWh/m² to a high of 5.58 kWh/m² in May across the year — August's 5.22 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.4Bright
85.4Bright
95.4Bright
105.4Bright
115.3Bright
125.3Bright
135.3Bright
145.3Bright
155.2Bright
165.2Bright
175.2Bright
185.2Bright
195.1Bright
205.1Bright
215.1Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
264.9Bright
274.9Bright
284.8Bright
294.8Bright
304.8Bright
314.7Bright
Planning a trip in August

Hazard calendar for Innoshima

In seasonPeak

In August, Innoshima sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Innoshima 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 August a good time to visit Innoshima?

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

5.3
Sightseeing
8th-best month of the year
7.1
Beach & pool
1st-best month of the year

August is a reasonable time to visit Innoshima for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Innoshima in August

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

In August, Innoshima sees daytime highs around 30°C and nights near 26°C. Pack light clothes. Worth having: rain gear and sun protection. About 8 days see rain.

light clothesrain gearsun protection

Sea temperature near Innoshima in August

The nearest coast averages about 28°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 18 km away) is warmest in August at about 28°C and coldest in February near 13°C.

It's comfortable for a long swim from Jun 3 to Nov 14 — about 5.4 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb13Bracing
Mar13Bracing
Apr15Cool
May18Cool
Jun22Refreshing
Jul25Warm
Aug28Warm
Sep27Warm
Oct24Refreshing
Nov20Cool
Dec17Cool

UV index in Innoshima in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August 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 Innoshima peaks around July 15 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJul 15UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May8Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Innoshima in August

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Innoshima is worst in April — around 24 µg/m³ PM2.5 (moderate), about 1.7× the cleanest month (December, 14 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1324 µg/m³Dec 1414 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb19Moderate
Mar23Moderate
Apr24Moderate
May22Moderate
Jun20Moderate
Jul17Moderate
Aug17Moderate
Sep16Moderate
Oct14Moderate
Nov15Moderate
Dec14Moderate
Location & terrain

Where is Innoshima?

Innoshima sits at 34.3°N, 133.2°E, 33 m above sea level, in Japan. The nearest listed city is Onomichi, 15 km away.

Topography around Innoshima

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

Within 3 km, the terrain around Innoshima has significant variations in elevation — a maximum elevation change of 379 m around an average of 32 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 473 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,900 m.

The land around Innoshima is covered by water (45%) and trees (40%) within 3 km, water (66%) and trees (27%) within 16 km, and trees (62%) and water (26%) within 80 km.

3 km
379 m
16 km
473 m
80 km
1,900 m
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Onomichi 15 km · Mihara 16 km · Takehara 25 km · Fukuyama 28 km · Imabari 29 km · Shin’ichi 31 km · Fuchūchō 33 km · Kōzan 36 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 Innoshima (34.2833°, 133.1833°, elevation 33 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).