Yamaguchi weather in August

In August, Yamaguchi sees average daytime highs of 31°C and overnight lows near 24°C, with 167 mm of rain across 14.2 wet days and about 13.3 hours of daylight. It is the 1st-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 32°C in the first days to 30°C by the end. The sky is clear or mostly clear about 27% 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 Yamaguchi's 8th-clearest and 9th-windiest month. For the whole year in context, see Yamaguchi's year-round climate.

Daytime high
31°
1st warmest
Overnight low
24°
12th coldest
Rainfall
167 mm
14.2 wet days
Daylight
13 h 18 min
5:40 AM – 6:57 PM
Cloud cover
63%
8th clearest
Wind
9 km/h
9th windiest
Solar energy
5.19 kWh/m²
Travel score
3.9
out of 10

Yamaguchi is capital city of Yamaguchi prefecture.

Density
190/km²
people per km²
Founded
1929

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 32°C in the first days to 30°C by the end.

A typical August day in Yamaguchi reaches about 31°C in the afternoon and slips back to 24°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 34°C. Set against its neighbours, August runs about 2°C warmer than July and about 4°C warmer than September.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13224
23224
33224
43224
53224
63224
73224
83224
93224
103224
113224
123224
133224
143224
153224
163124
173124
183124
193124
203124
213124
223124
233123
243123
253123
263123
273023
283023
293023
303023
313022

How August really feels in Yamaguchi

Once humidity and wind are folded in, August averages 31 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
31
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.

Yamaguchi weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 629.72.2101.7
Feb10° / 709.81.810.72.2
Mar14° / 11711.40.411.73.8
Apr19° / 13010.6012.85.9
May23° / 14°15010.5013.86.7
Jun26° / 19°24914.3014.25.7
Jul30° / 23°28316.30144.2
Aug31° / 24°16714.2013.33.9
Sep28° / 20°17812.4012.25.7
Oct23° / 14°978.1011.17.1
Nov17° / 788.2010.25.6
Dec11° / 649.70.99.82.9

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 17% of August, with mostly cloudy or overcast conditions the remaining 55%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24852
34852
44753
54753
64753
74555
84555
94555
104456
114456
124456
134357
144357
154357
164555
174555
184555
194555
204555
214456
224456
234456
244456
254357
264357
274357
284456
294357
304357
314357

Chance of precipitation in August

Any precipitation

Yamaguchi gets around 167 mm of rain over 14.2 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 46% and peaks near 48% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
145
244
344
444
544
644
744
845
945
1046
1146
1247
1347
1447
1548
1648
1748
1848
1948
2048
2147
2247
2347
2447
2546
2646
2746
2846
2946
3046
3146

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 67% of days. Sticky, muggy-or-worse air turns up on roughly 96% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
101107316
20197317
30197317
40197317
50197317
60197317
70197317
80197317
901107217
1001107217
1101107217
1201107217
1301107217
1411117017
1511117116
1612126916
1712136816
1812146815
1913156615
2013166614
2113176613
2214186512
2315196411
2415206311
2516216210
261723609
271824589
281925578
2911026567
3011127547
3111228536

Wind in August

Winds average 9 km/h in August.

Across August, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
189calm
199calm
209calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

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 5:28 AM to 5:51 AM, and sunset from 7:12 PM to 6:38 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:287:12
213.75:297:11
313.75:307:10
413.65:317:09
513.65:317:08
613.65:327:07
713.65:337:06
813.55:347:05
913.55:347:04
1013.55:357:03
1113.45:367:02
1213.45:377:01
1313.45:377:00
1413.35:386:59
1513.35:396:58
1613.35:406:57
1713.35:406:56
1813.25:416:54
1913.25:426:53
2013.25:436:52
2113.15:436:51
2213.15:446:50
2313.15:456:48
2413.05:466:47
2513.05:466:46
2613.05:476:44
2712.95:486:43
2812.95:486:42
2912.95:496:40
3012.85:506:39
3112.85:516:38

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.19 kWh/m².

For context, solar energy here swings from a low near 2.17 kWh/m² to a high of 5.6 kWh/m² in May across the year — August's 5.19 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
75.5Bright
85.4Bright
95.4Bright
105.4Bright
115.3Bright
125.3Bright
135.3Bright
145.3Bright
155.2Bright
165.2Bright
175.2Bright
185.1Bright
195.1Bright
205.1Bright
215.0Bright
225.0Bright
235.0Bright
244.9Bright
254.9Bright
264.9Bright
274.8Bright
284.8Bright
294.8Bright
304.7Bright
314.7Bright
Planning a trip in August

Hazard calendar for Yamaguchi

In seasonPeak

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

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

Yamaguchi's rainy season runs April–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 August a good time to visit Yamaguchi?

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

3.9
Sightseeing
8th-best month of the year
5.9
Beach & pool
2nd-best month of the year

August is a weaker month for outdoor sightseeing in Yamaguchi.

What to pack for Yamaguchi in August

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

In August, Yamaguchi sees daytime highs around 31°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 14 days see rain.

light clothesrain gearsun protection

Sea temperature near Yamaguchi in August

The nearest coast averages about 27°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 35 km away) is warmest in August at about 27°C and coldest in February near 12°C.

It's comfortable for a long swim from Jun 7 to Nov 11 — about 5.2 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb12Bracing
Mar12Bracing
Apr14Bracing
May17Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov20Cool
Dec16Cool

UV index in Yamaguchi 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 Yamaguchi peaks around June 21 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 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 highModerateJun 21UV 10Dec 21UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr7Very high
May8Very high
Jun10Very high
Jul10Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Yamaguchi 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 Yamaguchi is worst in April — around 23 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateApr 1023 µg/m³Oct 1111 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb19Moderate
Mar23Moderate
Apr23Moderate
May20Moderate
Jun16Moderate
Jul13Moderate
Aug15Moderate
Sep11Good
Oct11Good
Nov13Moderate
Dec12Moderate
Location & terrain

Where is Yamaguchi?

Yamaguchi sits at 34.2°N, 131.5°E, 157 m above sea level, in Japan. The nearest listed city is Ogōri-shimogō, 11 km away.

Topography around Yamaguchi

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

Within 3 km, the terrain around Yamaguchi has significant variations in elevation — a maximum elevation change of 424 m around an average of 118 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 780 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,369 m.

The land around Yamaguchi is covered by trees (60%) and artificial surfaces (35%) within 3 km, trees (83%) within 16 km, and water (51%) and trees (42%) within 80 km.

3 km
424 m
16 km
780 m
80 km
1,369 m
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Ogōri-shimogō 11 km · Hōfu 17 km · Mine 23 km · Hagi 25 km · Sanyōonoda 33 km · Onoda 33 km · Nagato 33 km · Ube 33 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 Yamaguchi (34.1833°, 131.4667°, elevation 157 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).