Agano weather in August

In August, Agano sees average daytime highs of 29°C and overnight lows near 22°C, with 215 mm of rain across 17.8 wet days and about 13.5 hours of daylight. It is the 1st-warmest and 2nd-wettest month of the year here.

Highs ease over the month, from about 30°C in the first days to 28°C by the end. The sky is clear or mostly clear about 24% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 14 hours at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Agano's 2nd-clearest and 11th-windiest month. For the whole year in context, see Agano's year-round climate.

Daytime high
29°
1st warmest
Overnight low
22°
12th coldest
Rainfall
215 mm
17.8 wet days
Daylight
13 h 30 min
5:03 AM – 6:31 PM
Cloud cover
64%
2nd clearest
Wind
6 km/h
11th windiest
Solar energy
4.95 kWh/m²
Travel score
4.5
out of 10

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 28°C by the end.

A typical August day in Agano reaches about 29°C in the afternoon and slips back to 22°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 33°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)
13022
23022
33022
43022
53022
63022
73022
83022
93022
103022
113022
122922
132922
142922
152922
162922
172922
182922
192922
202921
212921
222921
232921
242921
252821
262821
272821
282821
292821
302820
312820

How August really feels in Agano

Once humidity and wind are folded in, August averages 14 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
14
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.

Agano weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -2°19926.122.69.70.0
Feb / -2°1442218.510.50.0
Mar / 15621.211.611.71.0
Apr15° / 12915.91.712.93.8
May21° / 11°14014.30145.7
Jun24° / 16°18215014.65.8
Jul28° / 21°31119.8014.44.7
Aug29° / 22°21517.8013.54.5
Sep25° / 17°17616.2012.35.6
Oct19° / 11°16916.70115.1
Nov12° / 16719.32102.6
Dec / 20524.614.69.40.4

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 24% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 18% of August, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14060
24060
34060
44159
54159
64159
74159
84159
94159
104258
114258
124258
134258
144258
154357
164357
174357
184456
194357
204357
214456
224456
234357
244357
254357
264258
274258
284258
294159
304159
314159

Chance of precipitation in August

Any precipitation

Agano gets around 215 mm of rain over 17.8 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 57% and peaks near 60% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
153
253
353
453
553
653
754
854
954
1055
1155
1256
1356
1457
1557
1658
1758
1859
1959
2059
2160
2260
2360
2460
2560
2659
2759
2859
2959
3058
3158

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 89% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
11622692
21622683
30622693
40622684
50622684
60622684
71622674
81623655
91623655
101623655
111724635
121725625
131725634
141726624
151727614
161827613
172828593
182828593
192929573
2021030562
2121031552
2221132532
2331233502
2431234492
2531335472
2631437442
2731538422
2831639401
2931741381
3031842361
3141942331

Wind in August

Winds average 6 km/h in August.

Across August, daily wind ranges from about 6 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 hours 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 66 minutes over August. Sunrise moves from 4:50 AM to 5:16 AM, and sunset from 6:48 PM to 6:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.04:506:48
213.94:516:47
313.94:526:46
413.94:526:45
513.94:536:44
613.84:546:43
713.84:556:42
813.84:566:41
913.74:576:40
1013.74:586:39
1113.74:596:38
1213.64:596:36
1313.65:006:35
1413.55:016:34
1513.55:026:33
1613.55:036:31
1713.45:046:30
1813.45:056:29
1913.45:066:27
2013.35:076:26
2113.35:076:25
2213.25:086:23
2313.25:096:22
2413.25:106:20
2513.15:116:19
2613.15:126:18
2713.15:136:16
2813.05:146:15
2913.05:146:13
3012.95:156:12
3112.95:166:10

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.95 kWh/m².

For context, solar energy here swings from a low near 1.68 kWh/m² to a high of 5.51 kWh/m² in May across the year — August's 4.95 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.3Bright
45.3Bright
55.3Bright
65.2Bright
75.2Bright
85.2Bright
95.2Bright
105.1Bright
115.1Bright
125.1Bright
135.0Bright
145.0Bright
155.0Bright
164.9Bright
174.9Bright
184.9Bright
194.8Bright
204.8Bright
214.8Bright
224.7Bright
234.7Bright
244.7Bright
254.7Bright
264.6Bright
274.6Bright
284.5Bright
294.5Bright
304.5Bright
314.4Bright
Planning a trip in August

Hazard calendar for Agano

In seasonPeak

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

Agano 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 Agano?

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

4.5
Sightseeing
6th-best month of the year
5.7
Beach & pool
1st-best month of the year

August is a reasonable time to visit Agano for sightseeing.

What to pack for Agano in August

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

In August, Agano sees daytime highs around 29°C and nights near 22°C. Pack light clothes and rain gear. Worth having: sun protection. About 18 days see rain.

light clothesrain gearsun protection

Sea temperature near Agano in August

The nearest coast averages about 26°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 31 km away) is warmest in August at about 26°C and coldest in March near 10°C.

It's comfortable for a long swim from Jun 22 to Oct 30 — about 4.3 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan12Bracing
Feb10Bracing
Mar10Bracing
Apr11Bracing
May15Bracing
Jun19Cool
Jul23Refreshing
Aug26Warm
Sep25Warm
Oct22Refreshing
Nov18Cool
Dec15Cool

UV index in Agano 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 Agano peaks around August 13 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 13UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun8Very high
Jul9Very high
Aug9Very high
Sep8Very high
Oct5Moderate
Nov3Moderate
Dec2Low

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

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1623 µg/m³Dec 1711 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb15Moderate
Mar22Moderate
Apr23Moderate
May22Moderate
Jun18Moderate
Jul16Moderate
Aug14Moderate
Sep13Moderate
Oct13Moderate
Nov12Good
Dec11Good
Location & terrain

Where is Agano?

Agano sits at 37.8°N, 139.2°E, 7 m above sea level, in Japan. The nearest listed city is Suibara, 1.0 km away.

Topography around Agano

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

Within 3 km, the terrain around Agano has only modest variations in elevation — a maximum elevation change of 16 m around an average of 7 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 970 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,110 m.

The land around Agano is covered by cropland (73%) within 3 km, cropland (39%) and trees (34%) within 16 km, and trees (54%) and water (33%) within 80 km.

3 km
16 m
16 km
970 m
80 km
2,110 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Suibara 1.0 km · Niitsu-honchō 10 km · Kameda-honchō 11 km · Gosen 12 km · Shibata 16 km · Muramatsu 17 km · Niigata 19 km · Shirone 19 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 Agano (37.8361°, 139.2233°, elevation 7 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).