Otaru weather in May

In May, Otaru sees average daytime highs of 12°C and overnight lows near 7°C, with 84 mm of precipitation across 11.7 wet days and about 14.4 hours of daylight. It is the 6th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 10°C in the first days to 14°C by the end. The sky is clear or mostly clear about 30% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 54 min at the start of May to 14 h 54 min by month's end. Set against the rest of the year, May is Otaru's 3rd-clearest and 9th-windiest month. For the whole year in context, see Otaru's year-round climate.

Daytime high
12°
6th warmest
Overnight low
7th coldest
Precipitation
84 mm
11.7 wet days
Daylight
14 h 30 min
4:18 AM – 6:46 PM
Cloud cover
62%
3rd clearest
Wind
12 km/h
9th windiest
Solar energy
5.59 kWh/m²
Travel score
3.0
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 10°C in the first days to 14°C by the end.

A typical May day in Otaru reaches about 12°C in the afternoon and slips back to 7°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 8°C and 16°C. Set against its neighbours, May runs about 5°C warmer than April and about 5°C cooler than June.

10°15°20°151015202531
Avg high (°C)Avg low (°C)
194
294
3104
4105
5105
6105
7105
8105
9116
10116
11116
12116
13116
14127
15127
16127
17127
18127
19138
20138
21138
22138
23138
24149
25149
26149
27149
28149
29149
301510
311510

How May really feels in Otaru

Once humidity and wind are folded in, May 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

May 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 May compares with the rest of the year at a glance. May is the 6th-warmest and 8th-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 May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 13% of May, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14555
24456
34357
44357
54258
64258
74159
84159
94159
104060
114159
124159
134258
144258
154258
164258
174258
184258
194258
204357
214456
224456
234456
244456
254456
264456
274555
284555
294555
304555
314456

Chance of precipitation in May

Any precipitationSnow

Otaru gets around 84 mm of rain and snow over 11.7 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 38% and peaks near 38% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
1376
2375
3375
4374
5374
6383
7383
8383
9382
10382
11382
12382
13381
14381
15381
16381
17381
18380
19380
20380
21380
22380
23370
24370
25380
26380
27380
28380
29380
30380
31380

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
31000
41000
51000
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
27991
28991
29991
30991
31982

Wind in May

Winds average 12 km/h in May.

Across May, daily wind ranges from about 11 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
113light breeze
213light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212calm
1312calm
1412calm
1512calm
1612calm
1712calm
1812calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm
3111calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 54 min at the start of May to 14 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 4:37 AM to 4:06 AM, and sunset from 6:29 PM to 7:01 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.94:376:29
213.94:366:31
314.04:346:32
414.04:336:33
514.04:316:34
614.14:306:35
714.14:296:36
814.24:276:38
914.24:266:39
1014.24:256:40
1114.34:246:41
1214.34:236:42
1314.44:216:43
1414.44:206:44
1514.44:196:45
1614.54:186:46
1714.54:176:48
1814.54:166:49
1914.64:156:50
2014.64:146:51
2114.64:136:52
2214.74:126:53
2314.74:116:54
2414.74:116:55
2514.84:106:56
2614.84:096:57
2714.84:086:58
2814.84:086:58
2914.94:076:59
3014.94:067:00
3114.94:067:01

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.59 kWh/m² — the sunniest month for solar.

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 — May's 5.59 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.5Bright
85.5Bright
95.5Bright
105.5Bright
115.5Bright
125.5Bright
135.5Bright
145.5Bright
155.5Bright
165.5Bright
175.6Bright
185.6Bright
195.6Bright
205.6Bright
215.6Bright
225.6Bright
235.7Bright
245.7Bright
255.7Bright
265.7Bright
275.7Bright
285.7Bright
295.8Bright
305.8Bright
315.8Bright
Planning a trip in May

Hazard calendar for Otaru

In seasonPeak

In May, 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 May a good time to visit Otaru?

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

3.0
Sightseeing
6th-best month of the year
0.0
Beach & pool
6th-best month of the year

May is a weaker month for outdoor sightseeing in Otaru.

What to pack for Otaru in May

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

In May, Otaru sees daytime highs around 12°C and nights near 7°C. Worth packing: a warm layer, rain gear and sun protection. About 12 days see rain.

a warm layerrain gearsun protection

Sea temperature near Otaru in May

The nearest coast averages about 10°C in May — 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 May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. 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 May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May 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
May 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).