Shimonoseki weather in August

In August, Shimonoseki sees average daytime highs of 28°C and overnight lows near 26°C, with 139 mm of rain across 11.4 wet days and about 13.3 hours of daylight. It is the 1st-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 35% of the time in August, and the air most often feels miserable.

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 Shimonoseki's 5th-clearest and 10th-windiest month. For the whole year in context, see Shimonoseki's year-round climate.

Daytime high
28°
1st warmest
Overnight low
26°
12th coldest
Rainfall
139 mm
11.4 wet days
Daylight
13 h 18 min
5:42 AM – 6:59 PM
Cloud cover
58%
5th clearest
Wind
14 km/h
10th windiest
Solar energy
5.13 kWh/m²
Travel score
5.7
out of 10

Shimonoseki is city in Yamaguchi Prefecture, Japan.

Density
371/km²
people per km²
Founded
1889

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical August day in Shimonoseki reaches about 28°C in the afternoon and slips back to 26°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 30°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)
12826
22826
32926
42926
52926
62926
72926
82926
92926
102926
112926
122926
132926
142926
152926
162926
172826
182826
192826
202826
212826
222825
232825
242825
252825
262825
272825
282825
292825
302825
312725

How August really feels in Shimonoseki

Once humidity and wind are folded in, August averages 21 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
21
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.

Shimonoseki weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 9213.91.5101.6
Feb / 91121.210.71.8
Mar12° / 14412.40.211.73.0
Apr16° / 12°15311012.84.8
May20° / 17°17010.4013.76.2
Jun23° / 20°27313.8014.25.9
Jul27° / 24°25513.50145.8
Aug28° / 26°13911.4013.35.7
Sep26° / 23°16311.5012.26.5
Oct21° / 18°1048.4011.16.9
Nov16° / 13°9510.2010.25.2
Dec11° / 9012.80.59.82.7

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 14% of August, with mostly cloudy or overcast conditions the remaining 51%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15446
25446
35347
45347
55347
65248
75149
85050
95050
105050
114852
124951
134753
144753
154753
164753
174753
184753
194852
204951
214951
224951
235050
244852
254852
264852
274753
284852
294753
304753
314753

Chance of precipitation in August

Any precipitation

Shimonoseki gets around 139 mm of rain over 11.4 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 37% and peaks near 41% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
132
232
332
432
532
632
732
833
933
1034
1134
1235
1336
1437
1538
1638
1739
1839
1940
2040
2140
2240
2340
2441
2541
2641
2741
2841
2941
3041
3141

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the miserable band about 50% of days. Sticky, muggy-or-worse air turns up on roughly 99% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1043462
2033364
3033364
4033364
5033364
6033364
7033364
8033463
9033463
10033562
11033661
12033760
13033859
14133957
15134056
16144154
17144253
18154351
19164449
20264547
21274545
22284643
232104741
242114839
253124837
263134935
273154933
283164931
294184929
304204927
314214925

Wind in August

Winds average 14 km/h in August.

Across August, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
113light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze
3114light breeze

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 5:31 AM to 5:53 AM, and sunset from 7:14 PM to 6:40 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:317:14
213.75:327:13
313.75:337:12
413.65:337:11
513.65:347:10
613.65:357:09
713.55:357:08
813.55:367:07
913.55:377:06
1013.55:387:05
1113.45:387:04
1213.45:397:03
1313.45:407:02
1413.35:417:01
1513.35:417:00
1613.35:426:59
1713.25:436:57
1813.25:446:56
1913.25:446:55
2013.15:456:54
2113.15:466:53
2213.15:466:51
2313.05:476:50
2413.05:486:49
2513.05:496:48
2612.95:496:46
2712.95:506:45
2812.95:516:44
2912.85:526:42
3012.85:526:41
3112.85:536:40

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.13 kWh/m².

For context, solar energy here swings from a low near 2.12 kWh/m² to a high of 5.54 kWh/m² in May across the year — August's 5.13 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
65.4Bright
75.4Bright
85.4Bright
95.3Bright
105.3Bright
115.3Bright
125.3Bright
135.2Bright
145.2Bright
155.2Bright
165.1Bright
175.1Bright
185.1Bright
195.0Bright
205.0Bright
215.0Bright
224.9Bright
234.9Bright
244.9Bright
254.8Bright
264.8Bright
274.8Bright
284.7Bright
294.7Bright
304.7Bright
314.6Bright
Planning a trip in August

Hazard calendar for Shimonoseki

In seasonPeak

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

Shimonoseki 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 Shimonoseki?

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

5.7
Sightseeing
6th-best month of the year
6.7
Beach & pool
1st-best month of the year

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

What to pack for Shimonoseki in August

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

In August, Shimonoseki sees daytime highs around 28°C and nights near 26°C. Pack light clothes. Worth having: rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near Shimonoseki 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 20 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 6 to Nov 10 — 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
Nov19Cool
Dec16Cool

UV index in Shimonoseki 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 Shimonoseki peaks around July 17 at about 9 (very high) — 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 highModerateJul 17UV 9Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr8Very high
May8Very high
Jun9Very high
Jul9Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Shimonoseki 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 Shimonoseki is worst in March — around 27 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 12 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 2026 µg/m³Oct 1212 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb20Moderate
Mar27Moderate
Apr24Moderate
May21Moderate
Jun18Moderate
Jul16Moderate
Aug19Moderate
Sep13Moderate
Oct12Good
Nov14Moderate
Dec13Moderate
Location & terrain

Where is Shimonoseki?

Shimonoseki sits at 34.0°N, 130.9°E, 10 m above sea level, in Japan. The nearest listed city is Kitakyushu, 14 km away.

Topography around Shimonoseki

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

Within 3 km, the terrain around Shimonoseki has significant variations in elevation — a maximum elevation change of 291 m around an average of 26 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 658 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,205 m.

The land around Shimonoseki is covered by artificial surfaces (42%), water (34%) and trees (22%) within 3 km, water (53%), trees (22%) and artificial surfaces (20%) within 16 km, and water (50%) and trees (38%) within 80 km.

3 km
291 m
16 km
658 m
80 km
1,205 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Kitakyushu 14 km · Kanda 20 km · Sanyōonoda 22 km · Onoda 23 km · Miyaodai 24 km · Yukuhashi 26 km · Nakama 26 km · Miyako 29 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 Shimonoseki (33.9555°, 130.9371°, elevation 10 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).