Otaru weather in August

In August, Otaru sees average daytime highs of 23°C and overnight lows near 19°C, with 163 mm of rain across 14.2 wet days and about 13.8 hours of daylight. It is the 1st-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 23°C through the month. The sky is clear or mostly clear about 23% of the time in August, and the air most often feels muggy.

Daylight stretches from about 14 h 24 min at the start of August to 13 h 06 min by month's end. Set against the rest of the year, August is Otaru's 7th-clearest and 10th-windiest month. For the whole year in context, see Otaru's year-round climate.

Daytime high
23°
1st warmest
Overnight low
19°
12th coldest
Rainfall
163 mm
14.2 wet days
Daylight
13 h 48 min
4:47 AM – 6:34 PM
Cloud cover
67%
7th clearest
Wind
10 km/h
10th windiest
Solar energy
4.54 kWh/m²
Travel score
6.0
out of 10

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 23°C through the month.

A typical August day in Otaru reaches about 23°C in the afternoon and slips back to 19°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 20°C and 26°C. Set against its neighbours, August runs about 2°C warmer than July and about 3°C warmer than September.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12319
22319
32319
42319
52319
62319
72319
82319
92319
102319
112319
122319
132319
142319
152319
162319
172319
182319
192319
202319
212319
222319
232319
242319
252219
262219
272218
282218
292218
302218
312218

How August really feels in Otaru

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.

Otaru weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-3° / -6°9820.824.29.20.0
Feb-2° / -6°791820.210.20.0
Mar / -3°761515.411.60.0
Apr / 6611.2513.10.7
May12° / 8411.70.414.43.0
Jun17° / 12°7610.6015.15.1
Jul21° / 17°12712.8014.95.9
Aug23° / 19°16314.2013.86.0
Sep20° / 16°14913.9012.35.6
Oct14° / 11714.90.610.83.5
Nov / 12918.611.29.50.7
Dec-0° / -3°12621.922.58.90.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 15% of August, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23862
33862
43862
53961
63961
73862
83862
93763
103862
113862
123763
133763
143763
153763
163664
173763
183763
193763
203763
213763
223763
233763
243862
253862
264060
274060
284060
294060
304159
314159

Chance of precipitation in August

Any precipitation

Otaru gets around 163 mm of rain over 14.2 wet days in August, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 46% and peaks near 48% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
142
242
343
443
544
644
745
845
946
1046
1147
1247
1348
1448
1548
1648
1748
1848
1948
2048
2147
2247
2347
2446
2546
2646
2746
2845
2945
3045
3145

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the muggy band about 37% of days. Sticky, muggy-or-worse air turns up on roughly 47% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1112324411
2112314412
3212304412
4212304413
5212304314
6212304314
7212304314
8211314214
9211324214
10211324114
11211334113
12211344013
13211354013
14211354012
15211363911
16211363911
17312373910
1831337389
1931438379
2031538368
2131638367
2231738357
2341838346
2441939336
2542039325
2642138315
2752238305
2852438294
2952538284
3062638273
3172738263

Wind in August

Winds average 10 km/h in August.

Across August, daily wind ranges from about 9 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm
3111calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 24 min at the start of August to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 78 minutes over August. Sunrise moves from 4:30 AM to 5:03 AM, and sunset from 6:54 PM to 6:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.44:306:54
214.44:316:53
314.34:326:52
414.34:336:50
514.24:346:49
614.24:356:48
714.24:366:47
814.14:386:45
914.14:396:44
1014.04:406:42
1114.04:416:41
1214.04:426:40
1313.94:436:38
1413.94:446:37
1513.84:456:35
1613.84:476:34
1713.74:486:32
1813.74:496:31
1913.74:506:29
2013.64:516:27
2113.64:526:26
2213.54:536:24
2313.54:546:22
2413.44:566:21
2513.44:576:19
2613.34:586:17
2713.34:596:16
2813.25:006:14
2913.25:016:12
3013.15:026:10
3113.15:036:09

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.54 kWh/m².

For context, solar energy here swings from a low near 1.4 kWh/m² to a high of 5.59 kWh/m² in May across the year — August's 4.54 kWh/m² falls in the middle.

024151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.8Bright
34.8Bright
44.8Bright
54.8Bright
64.8Bright
74.7Bright
84.7Bright
94.7Bright
104.7Bright
114.6Bright
124.6Bright
134.6Bright
144.5Bright
154.5Bright
164.5Bright
174.5Bright
184.5Bright
194.5Bright
204.4Bright
214.4Bright
224.4Bright
234.4Bright
244.4Bright
254.4Bright
264.4Bright
274.3Bright
284.3Bright
294.3Bright
304.3Bright
314.3Bright
Planning a trip in August

Hazard calendar for Otaru

In seasonPeak

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

Otaru 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 Otaru?

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

6.0
Sightseeing
1st-best month of the year
4.5
Beach & pool
1st-best month of the year

August is a reasonable time to visit Otaru for sightseeing.

What to pack for Otaru in August

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

In August, Otaru sees daytime highs around 23°C and nights near 19°C. Pack rain gear. Worth having: light clothes and sun protection. About 14 days see rain.

rain gearlight clothessun protection

Sea temperature near Otaru in August

The nearest coast averages about 22°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 23 km away) is warmest in August at about 22°C and coldest in February near 6°C.

It's comfortable for a long swim from Jul 31 to Sep 22 — about 1.8 months when the water holds above 20°C.

10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan7Bracing
Feb6Bracing
Mar6Bracing
Apr7Bracing
May10Bracing
Jun14Bracing
Jul19Cool
Aug22Refreshing
Sep21Refreshing
Oct17Cool
Nov13Bracing
Dec9Bracing

UV index in Otaru in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Otaru peaks around August 18 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 1 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighHighVery highHighModerateLowAug 18UV 8Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar3Moderate
Apr5High
May7Very high
Jun7High
Jul5Moderate
Aug8Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Otaru 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 Otaru is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1121 µg/m³Dec 169 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb15Moderate
Mar21Moderate
Apr21Moderate
May19Moderate
Jun13Moderate
Jul12Moderate
Aug11Good
Sep10Good
Oct12Good
Nov11Good
Dec9Good
Location & terrain

Where is Otaru?

Otaru sits at 43.2°N, 141.0°E, 30 m above sea level, in Japan. The nearest listed city is Yoichi, 19 km away.

Topography around Otaru

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

Within 3 km, the terrain around Otaru has significant variations in elevation — a maximum elevation change of 508 m around an average of 83 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,289 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,867 m.

The land around Otaru is covered by trees (44%), artificial surfaces (32%) and water (23%) within 3 km, water (49%) and trees (46%) within 16 km, and trees (48%) and water (37%) within 80 km.

3 km
508 m
16 km
1,289 m
80 km
1,867 m
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Yoichi 19 km · Ishikari 29 km · Sapporo 31 km · Kutchan 38 km · Tōbetsu 42 km · Ebetsu 45 km · Niseko 50 km · Kitahiroshima 52 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 Otaru (43.1894°, 141.0022°, elevation 30 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).