Nankoku weather in August

In August, Nankoku sees average daytime highs of 29°C and overnight lows near 25°C, with 218 mm of rain across 18.3 wet days and about 13.2 hours of daylight. It is the 1st-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 29% 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 Nankoku's 9th-clearest and 11th-windiest month. For the whole year in context, see Nankoku's year-round climate.

Daytime high
29°
1st warmest
Overnight low
25°
12th coldest
Rainfall
218 mm
18.3 wet days
Daylight
13 h 18 min
5:32 AM – 6:47 PM
Cloud cover
61%
9th clearest
Wind
8 km/h
11th windiest
Solar energy
5.43 kWh/m²
Travel score
4.4
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical August day in Nankoku reaches about 29°C in the afternoon and slips back to 25°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 31°C. Set against its neighbours, August runs about 1°C warmer than July and about 2°C warmer than September.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12925
22925
32925
42925
52925
62925
72925
83025
93025
103025
112925
122925
132925
142925
152925
162925
172925
182925
192925
202925
212925
222925
232925
242925
252925
262925
272925
282924
292924
302924
312924

How August really feels in Nankoku

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.

Nankoku 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 daysDaylight (hours)Travel score
Jan11° / 636102.8
Feb11° / 857.410.83.1
Mar14° / 14310.511.74.3
Apr19° / 12°17410.412.85.9
May22° / 16°20011.513.76.4
Jun25° / 21°32117.114.25.4
Jul28° / 24°32618.7144.6
Aug29° / 25°21818.313.24.4
Sep27° / 22°24715.212.25.6
Oct23° / 17°1839.911.27.0
Nov18° / 12°987.510.36.2
Dec13° / 755.79.84.1

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% 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 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24555
34555
44456
54456
64654
74654
84654
94555
104555
114555
124555
134555
144456
154555
164654
174654
184654
194753
204852
214852
224852
234852
244852
254753
264753
274753
284753
294753
304753
314753

Chance of precipitation in August

Any precipitation

Nankoku gets around 218 mm of rain over 18.3 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 58% and peaks near 59% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
159
259
359
458
558
658
758
858
958
1058
1158
1258
1358
1459
1559
1659
1759
1859
1959
2059
2159
2259
2359
2459
2559
2659
2758
2858
2958
3057
3157

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 57% of days. Sticky, muggy-or-worse air turns up on roughly 99% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1025840
2025741
3015742
4015643
5015643
6015544
7015544
8015445
9015445
10015445
11025345
12025345
13025444
14035344
15035443
16035542
17045541
18145540
19155539
20155737
21165736
22175834
23175933
24186031
25296029
262106127
272116126
282126224
293136222
303146320
313166219

Wind in August

Winds average 8 km/h in August.

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

0246810151015202531
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
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 5:21 AM to 5:42 AM, and sunset from 7:02 PM to 6:28 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:217:02
213.75:227:01
313.65:227:00
413.65:236:59
513.65:246:58
613.65:256:58
713.55:256:57
813.55:266:56
913.55:276:55
1013.45:276:54
1113.45:286:53
1213.45:296:52
1313.35:306:51
1413.35:306:49
1513.35:316:48
1613.35:326:47
1713.25:336:46
1813.25:336:45
1913.25:346:44
2013.15:356:43
2113.15:356:41
2213.15:366:40
2313.05:376:39
2413.05:386:38
2513.05:386:36
2612.95:396:35
2712.95:406:34
2812.95:406:32
2912.85:416:31
3012.85:426:30
3112.85:426:28

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.43 kWh/m².

For context, solar energy here swings from a low near 2.61 kWh/m² to a high of 5.61 kWh/m² in May across the year — August's 5.43 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.7Bright
25.7Bright
35.7Bright
45.6Bright
55.6Bright
65.6Bright
75.6Bright
85.6Bright
95.6Bright
105.5Bright
115.5Bright
125.5Bright
135.5Bright
145.5Bright
155.5Bright
165.4Bright
175.4Bright
185.4Bright
195.4Bright
205.3Bright
215.3Bright
225.3Bright
235.3Bright
245.2Bright
255.2Bright
265.2Bright
275.1Bright
285.1Bright
295.1Bright
305.0Bright
315.0Bright
Planning a trip in August

Hazard calendar for Nankoku

In seasonPeak

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

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

Nankoku's rainy season runs April–October, 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 Nankoku?

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

4.4
Sightseeing
8th-best month of the year
5.7
Beach & pool
2nd-best month of the year

August is a reasonable time to visit Nankoku for sightseeing.

What to pack for Nankoku in August

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

In August, Nankoku sees daytime highs around 29°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 18 days see rain.

light clothesrain gearsun protection

Sea temperature near Nankoku 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 22 km away) is warmest in August at about 28°C and coldest in February near 17°C.

It's comfortable for a long swim from May 6 to Dec 16 — about 7.4 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan18Cool
Feb17Cool
Mar17Cool
Apr19Cool
May21Refreshing
Jun23Refreshing
Jul26Warm
Aug28Warm
Sep27Warm
Oct25Warm
Nov23Refreshing
Dec20Refreshing

UV index in Nankoku 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 Nankoku peaks around June 23 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 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJun 23UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr7Very high
May9Very high
Jun10Extreme
Jul10Extreme
Aug9Very high
Sep10Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Nankoku 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 Nankoku is worst in April — around 22 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (October, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1321 µg/m³Oct 1311 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb16Moderate
Mar20Moderate
Apr22Moderate
May19Moderate
Jun16Moderate
Jul13Moderate
Aug12Moderate
Sep11Good
Oct11Good
Nov12Good
Dec11Good
Location & terrain

Where is Nankoku?

Nankoku sits at 33.6°N, 133.6°E, 14 m above sea level, in Japan. The nearest listed city is Tosayamadachō-nakano, 5.0 km away.

Topography around Nankoku

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

Within 3 km, the terrain around Nankoku has only modest variations in elevation — a maximum elevation change of 151 m around an average of 15 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,128 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,939 m.

The land around Nankoku is covered by cropland (48%) and artificial surfaces (36%) within 3 km, trees (49%) and water (29%) within 16 km, and trees (57%) and water (38%) within 80 km.

3 km
151 m
16 km
1,128 m
80 km
1,939 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Tosayamadachō-nakano 5.0 km · Yamashita 5.0 km · Kochi 11 km · Ino 20 km · Tosa 20 km · Aki 24 km · Susaki 38 km · Shikokuchūō 46 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 Nankoku (33.5694°, 133.6494°, elevation 14 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).