Shonai weather in August

In August, Shonai sees average daytime highs of 27°C and overnight lows near 21°C, with 200 mm of rain across 17.3 wet days and about 13.5 hours of daylight. It is the 1st-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 26°C by the end. The sky is clear or mostly clear about 21% of the time in August, and the air most often feels oppressive.

Daylight stretches from about 14 h 06 min at the start of August to 12 h 54 min by month's end. Set against the rest of the year, August is Shonai's 4th-clearest and 11th-windiest month. For the whole year in context, see Shonai's year-round climate.

Daytime high
27°
1st warmest
Overnight low
21°
12th coldest
Rainfall
200 mm
17.3 wet days
Daylight
13 h 30 min
4:59 AM – 6:30 PM
Cloud cover
67%
4th clearest
Wind
7 km/h
11th windiest
Solar energy
4.56 kWh/m²
Travel score
5.3
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 26°C by the end.

A typical August day in Shonai reaches about 27°C in the afternoon and slips back to 21°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 31°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)
12821
22822
32822
42822
52822
62822
72822
82822
92822
102822
112822
122821
132821
142821
152821
162821
172721
182721
192721
202721
212721
222721
232721
242721
252720
262720
272720
282720
292620
302620
312620

How August really feels in Shonai

Once humidity and wind are folded in, August averages 0 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

August sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Shonai weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -2°19026.224.99.60.0
Feb / -2°13521.719.710.50.0
Mar / 14320.313.711.70.5
Apr13° / 11815.12.8133.1
May19° / 11°12513.6014.15.5
Jun23° / 16°14413.5014.75.9
Jul26° / 20°24718.2014.45.3
Aug27° / 21°20017.3013.55.3
Sep24° / 17°17015.8012.35.6
Oct18° / 11°17516.50114.8
Nov11° / 17319.54.59.92.2
Dec / 20625.118.19.30.2

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% 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 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23862
33862
43862
54060
64060
74060
83961
93961
104060
113961
123961
133862
143961
153961
163961
173862
183961
193961
203961
213961
223961
233961
243862
253862
263862
273862
283862
293862
303862
313763

Chance of precipitation in August

Any precipitation

Shonai gets around 200 mm of rain over 17.3 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 55% and peaks near 59% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
150
250
350
450
550
650
751
851
952
1053
1154
1254
1355
1456
1557
1658
1758
1859
1959
2059
2159
2259
2359
2459
2559
2659
2758
2858
2957
3057
3156

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 50% of days. Sticky, muggy-or-worse air turns up on roughly 83% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
12828593
22827603
32826613
42825623
52925604
62925604
73925594
83925594
93925594
1031025584
1131026574
1231027564
1331027564
1431128553
1541129533
1641129533
1741230513
1851231503
1951231493
2061332472
2161332462
2271433442
2371533432
2471534412
2571635402
2681735382
2781836362
2881937342
2982038322
3092138302
3192239282

Wind in August

Winds average 7 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.

0246810151015202531
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 06 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 72 minutes over August. Sunrise moves from 4:45 AM to 5:13 AM, and sunset from 6:48 PM to 6:08 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.14:456:48
214.04:466:47
314.04:476:46
414.04:486:45
513.94:496:44
613.94:496:43
713.94:506:42
813.84:516:40
913.84:526:39
1013.74:536:38
1113.74:546:37
1213.74:556:36
1313.64:566:34
1413.64:576:33
1513.64:586:32
1613.54:596:30
1713.55:006:29
1813.55:006:28
1913.45:016:26
2013.45:026:25
2113.35:036:23
2213.35:046:22
2313.35:056:20
2413.25:066:19
2513.25:076:18
2613.15:086:16
2713.15:096:15
2813.15:106:13
2913.05:116:11
3013.05:126:10
3112.95:136:08

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.56 kWh/m².

For context, solar energy here swings from a low near 1.62 kWh/m² to a high of 5.36 kWh/m² in May across the year — August's 4.56 kWh/m² falls in the middle.

024151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.9Bright
44.9Bright
54.9Bright
64.8Bright
74.8Bright
84.8Bright
94.8Bright
104.7Bright
114.7Bright
124.7Bright
134.6Bright
144.6Bright
154.6Bright
164.5Bright
174.5Bright
184.5Bright
194.5Bright
204.4Bright
214.4Bright
224.4Bright
234.4Bright
244.3Bright
254.3Bright
264.3Bright
274.3Bright
284.2Bright
294.2Bright
304.2Bright
314.2Bright
Planning a trip in August

Hazard calendar for Shonai

In seasonPeak

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

Shonai 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 Shonai?

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

5.3
Sightseeing
4th-best month of the year
5.5
Beach & pool
1st-best month of the year

August is a reasonable time to visit Shonai for sightseeing.

What to pack for Shonai in August

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

In August, Shonai sees daytime highs around 27°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 17 days see rain.

light clothesrain gearsun protection

Sea temperature near Shonai 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 24 km away) is warmest in August at about 26°C and coldest in March near 9°C.

It's comfortable for a long swim from Jun 25 to Oct 26 — about 4.1 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan12Bracing
Feb10Bracing
Mar9Bracing
Apr10Bracing
May14Bracing
Jun19Cool
Jul23Refreshing
Aug26Warm
Sep25Warm
Oct21Refreshing
Nov18Cool
Dec15Bracing

UV index in Shonai 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 Shonai peaks around August 17 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 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 highHighModerateLowAug 17UV 9Dec 19UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun8Very high
Jul7High
Aug9Very high
Sep7Very high
Oct5Moderate
Nov3Moderate
Dec2Low

Air quality in Shonai 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 Shonai is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1721 µg/m³Dec 159 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun15Moderate
Jul13Moderate
Aug11Good
Sep10Good
Oct10Good
Nov10Good
Dec9Good
Location & terrain

Where is Shonai?

Shonai sits at 38.8°N, 139.9°E, 7 m above sea level, in Japan. The nearest listed city is Sakata, 9.0 km away.

Topography around Shonai

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

Within 3 km, the terrain around Shonai has only modest variations in elevation — a maximum elevation change of 14 m around an average of 8 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 776 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,205 m.

The land around Shonai is covered by cropland (77%) within 3 km, cropland (37%) and trees (36%) within 16 km, and trees (55%) and water (35%) within 80 km.

3 km
14 m
16 km
776 m
80 km
2,205 m
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Sakata 9.0 km · Tsuruoka 16 km · Shinjō 36 km · Nikaho 47 km · Obanazawa 51 km · Yachi 59 km · Murayama 61 km · Yurihonjō 62 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 Shonai (38.8485°, 139.9031°, 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).