Jōetsu weather in August

In August, Jōetsu sees average daytime highs of 30°C and overnight lows near 24°C, with 122 mm of rain across 12.1 wet days and about 13.4 hours of daylight. It is the 1st-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 30°C in the first days to 29°C by the end. 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 54 min at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Jōetsu's 2nd-clearest and 11th-windiest month. For the whole year in context, see Jōetsu's year-round climate.

Daytime high
30°
1st warmest
Overnight low
24°
12th coldest
Rainfall
122 mm
12.1 wet days
Daylight
13 h 24 min
5:08 AM – 6:34 PM
Cloud cover
61%
2nd clearest
Wind
8 km/h
11th windiest
Solar energy
5.21 kWh/m²
Travel score
4.9
out of 10

Jōetsu is city in Niigata Prefecture, Japan.

Density
195/km²
people per km²
Founded
1971

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 30°C in the first days to 29°C by the end.

A typical August day in Jōetsu reaches about 30°C in the afternoon and slips back to 24°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 33°C. Set against its neighbours, August runs about 2°C warmer than July and about 4°C warmer than September.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13024
23024
33024
43024
53024
63024
73024
83024
93024
103024
113024
123024
133024
143024
153024
163024
173024
183024
193024
203024
213024
222923
232923
242923
252923
262923
272923
282923
292923
302923
312823

How August really feels in Jōetsu

Once humidity and wind are folded in, August averages 23 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
23
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.

Jōetsu weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 25325.916.39.70.2
Feb / 17821.213.310.60.3
Mar10° / 14519.66.511.71.6
Apr15° / 9713.40.412.94.3
May20° / 13°9211.60146.1
Jun24° / 18°11511.5014.56.4
Jul28° / 22°19114.4014.35.3
Aug30° / 24°12212.1013.44.9
Sep26° / 20°16214.1012.35.8
Oct20° / 14°16415.10115.6
Nov14° / 18018.50.3103.4
Dec / 24724.28.49.51.1

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 (%)
14654
24753
34753
44852
54852
64852
74852
84852
94753
104753
114753
124753
134753
144753
154753
164753
174753
184753
194753
204753
214753
224555
234555
244555
254555
264456
274456
284456
294258
304258
314258

Chance of precipitation in August

Any precipitation

Jōetsu gets around 122 mm of rain over 12.1 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 39% and peaks near 46% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
131
231
331
432
532
632
733
834
935
1035
1136
1237
1338
1439
1539
1640
1740
1841
1941
2042
2142
2243
2343
2444
2544
2644
2745
2845
2945
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 61% of days. Sticky, muggy-or-worse air turns up on roughly 95% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
101177210
201177210
301177111
401177111
501187011
601187011
702186911
802196811
902196811
1002206711
1102206711
1203216511
1303216511
1403216511
1504226311
1614226310
1714236210
181524619
191524619
201525618
211626598
221627597
231629577
241730566
251731565
261833535
271834534
281936504
2911037493
3011038473
3121139453

Wind in August

Winds average 8 km/h in August.

Across August, daily wind ranges from about 7 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
17calm
27calm
37calm
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 54 min at the start of August to 12 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 60 minutes over August. Sunrise moves from 4:55 AM to 5:21 AM, and sunset from 6:51 PM to 6:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.94:556:51
213.94:566:50
313.94:576:49
413.84:586:48
513.84:596:47
613.85:006:46
713.75:006:45
813.75:016:44
913.75:026:43
1013.65:036:42
1113.65:046:40
1213.65:056:39
1313.55:056:38
1413.55:066:37
1513.55:076:36
1613.45:086:34
1713.45:096:33
1813.45:106:32
1913.35:116:30
2013.35:116:29
2113.35:126:28
2213.25:136:26
2313.25:146:25
2413.15:156:24
2513.15:166:22
2613.15:176:21
2713.05:176:19
2813.05:186:18
2913.05:196:16
3012.95:206:15
3112.95:216:13

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.21 kWh/m².

For context, solar energy here swings from a low near 1.89 kWh/m² to a high of 5.79 kWh/m² in May across the year — August's 5.21 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.6Bright
25.6Bright
35.6Bright
45.6Bright
55.5Bright
65.5Bright
75.5Bright
85.5Bright
95.4Bright
105.4Bright
115.4Bright
125.3Bright
135.3Bright
145.3Bright
155.2Bright
165.2Bright
175.2Bright
185.1Bright
195.1Bright
205.0Bright
215.0Bright
225.0Bright
234.9Bright
244.9Bright
254.9Bright
264.8Bright
274.8Bright
284.8Bright
294.7Bright
304.7Bright
314.6Bright
Planning a trip in August

Hazard calendar for Jōetsu

In seasonPeak

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

Jōetsu 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 Jōetsu?

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

4.9
Sightseeing
6th-best month of the year
6.5
Beach & pool
1st-best month of the year

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

What to pack for Jōetsu in August

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

In August, Jōetsu sees daytime highs around 30°C and nights near 24°C. Pack light clothes. Worth having: rain gear and sun protection. About 12 days see rain.

light clothesrain gearsun protection

Sea temperature near Jōetsu 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 offshore is warmest in August at about 27°C and coldest in March near 10°C.

It's comfortable for a long swim from Jun 20 to Nov 1 — about 4.4 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb11Bracing
Mar10Bracing
Apr11Bracing
May15Bracing
Jun20Cool
Jul23Refreshing
Aug27Warm
Sep25Warm
Oct22Refreshing
Nov19Cool
Dec15Cool

UV index in Jōetsu in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks 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 Jōetsu peaks around August 12 at about 10 (very high) — 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 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 12UV 10Jan 1UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug10Very high
Sep9Very high
Oct5High
Nov3Moderate
Dec2Moderate

Air quality in Jōetsu 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 Jōetsu is worst in April — around 22 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1521 µg/m³Dec 149 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar20Moderate
Apr22Moderate
May20Moderate
Jun17Moderate
Jul15Moderate
Aug12Good
Sep10Good
Oct10Good
Nov10Good
Dec9Good
Location & terrain

Where is Jōetsu?

Jōetsu sits at 37.1°N, 138.2°E, 10 m above sea level, in Japan. The nearest listed city is Myoko, 14 km away.

Topography around Jōetsu

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

Within 3 km, the terrain around Jōetsu has only modest variations in elevation — a maximum elevation change of 177 m around an average of 22 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,200 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,900 m.

The land around Jōetsu is covered by artificial surfaces (46%), trees (24%) and cropland (20%) within 3 km, trees (39%) and water (32%) within 16 km, and trees (53%) and water (37%) within 80 km.

3 km
177 m
16 km
1,200 m
80 km
2,900 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Myoko 14 km · Arai 16 km · Iiyama 35 km · Itoigawa 37 km · Kashiwazaki 37 km · Nakano 46 km · Tōkamachi 47 km · Ojiya 53 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 Jōetsu (37.1483°, 138.2364°, 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).