Ōyama weather in May

In May, Ōyama sees average daytime highs of 20°C and overnight lows near 18°C, with 208 mm of rain across 11.6 wet days and about 13.8 hours of daylight. It is the 6th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 19°C in the first days to 21°C by the end. The sky is clear or mostly clear about 29% of the time in May, and the air most often feels humid.

Daylight stretches from about 13 h 24 min at the start of May to 14 h 06 min by month's end. Set against the rest of the year, May is Ōyama's 10th-clearest and 9th-windiest month. For the whole year in context, see Ōyama's year-round climate.

Daytime high
20°
6th warmest
Overnight low
18°
7th coldest
Rainfall
208 mm
11.6 wet days
Daylight
13 h 48 min
4:49 AM – 6:37 PM
Cloud cover
64%
10th clearest
Wind
21 km/h
9th windiest
Solar energy
5.59 kWh/m²
Travel score
6.0
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 19°C in the first days to 21°C by the end.

A typical May day in Ōyama reaches about 20°C in the afternoon and slips back to 18°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 18°C and 21°C. Set against its neighbours, May runs about 3°C warmer than April and about 3°C cooler than June.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
11816
21816
31916
41916
51916
61916
71917
81917
91917
101917
111917
121917
131917
141917
152017
162018
172018
182018
192018
202018
212018
222018
232018
242018
252019
262119
272119
282119
292119
302119
312119

Ōyama weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan11° / 948.39.92.8
Feb11° / 1129.310.72.9
Mar14° / 10°18012.911.73.7
Apr17° / 14°17711.812.85.1
May20° / 18°20811.613.86.0
Jun22° / 21°29014.514.35.6
Jul26° / 24°24013.614.16.1
Aug27° / 26°13713.213.36.2
Sep25° / 24°24015.612.25.9
Oct22° / 20°25914.111.16.1
Nov18° / 15°16012.110.25.6
Dec13° / 10°949.59.74.1

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 12% of May, with mostly cloudy or overcast conditions the remaining 59%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24753
34654
44654
54555
64456
74357
84357
94258
104258
114159
124060
134060
144060
153961
163961
173961
184060
194159
204159
214159
224159
234060
244060
254060
264060
273961
283862
293862
303763
313565

Chance of precipitation in May

Any precipitation

Ōyama gets around 208 mm of rain over 11.6 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 37% and peaks near 39% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
236
336
436
536
637
737
838
938
1038
1138
1239
1339
1438
1538
1638
1737
1837
1937
2036
2136
2236
2336
2436
2536
2635
2735
2835
2936
3036
3137

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the humid band about 35% of days. Sticky, muggy-or-worse air turns up on roughly 9% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
147322020
245332120
343332220
441342320
538342530
636352630
734362730
832362830
930372940
1028382940
1126393040
1225403150
1323403250
1421413360
1520413460
1618403570
1717403670
1815393880
1914383980
2013384090
21123741100
22113642110
23103543120
2493444131
2583345141
2673146151
2773047161
2862947171
2962748191
3052648201
3142548221

Wind in May

Winds average 21 km/h in May.

Across May, daily wind ranges from about 19 km/h on the calmest days to 23 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
123breezy
223breezy
323breezy
422breezy
522breezy
622breezy
722breezy
822breezy
922breezy
1022breezy
1122breezy
1222breezy
1321breezy
1421breezy
1521breezy
1621breezy
1721breezy
1821breezy
1921breezy
2020breezy
2120breezy
2220breezy
2320light breeze
2420light breeze
2520light breeze
2620light breeze
2720light breeze
2819light breeze
2919light breeze
3019light breeze
3119light breeze

Sunrise & sunset in May

DaylightNight

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

Days grow by about 42 minutes over May. Sunrise moves from 5:03 AM to 4:41 AM, and sunset from 6:25 PM to 6:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.45:036:25
213.45:026:26
313.45:016:27
413.55:006:28
513.54:596:29
613.54:586:30
713.64:576:30
813.64:566:31
913.64:556:32
1013.64:546:33
1113.74:536:34
1213.74:536:34
1313.74:526:35
1413.84:516:36
1513.84:506:37
1613.84:496:37
1713.84:496:38
1813.94:486:39
1913.94:476:40
2013.94:466:41
2113.94:466:41
2213.94:456:42
2314.04:456:43
2414.04:446:43
2514.04:436:44
2614.04:436:45
2714.14:426:46
2814.14:426:46
2914.14:426:47
3014.14:416:48
3114.14:416:48

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 2.6 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
145.6Bright
155.6Bright
165.6Bright
175.6Bright
185.6Bright
195.6Bright
205.7Bright
215.7Bright
225.7Bright
235.7Bright
245.7Bright
255.7Bright
265.7Bright
275.7Bright
285.7Bright
295.6Bright
305.6Bright
315.6Bright
Planning a trip in May

Hazard calendar for Ōyama

In seasonPeak

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

Ōyama 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 Ōyama?

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

6.0
Sightseeing
4th-best month of the year
2.9
Beach & pool
6th-best month of the year

May is a reasonable time to visit Ōyama for sightseeing.

What to pack for Ōyama in May

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

In May, Ōyama sees daytime highs around 20°C and nights near 18°C. Worth packing: rain gear, sun protection and a windbreaker. About 12 days see rain.

rain gearsun protectiona windbreaker

Sea temperature near Ōyama in May

The nearest coast averages about 19°C in May — 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 February near 16°C.

It's comfortable for a long swim from May 25 to Nov 29 — about 6.2 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb16Cool
Mar16Cool
Apr17Cool
May19Cool
Jun22Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Refreshing
Nov21Refreshing
Dec19Cool

UV index in Ōyama in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May 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 Ōyama peaks around July 22 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJul 22UV 10Dec 23UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May9Very high
Jun10Very high
Jul10Extreme
Aug10Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Ōyama 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 Ōyama 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).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1721 µg/m³Dec 159 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar19Moderate
Apr21Moderate
May19Moderate
Jun16Moderate
Jul12Good
Aug11Good
Sep10Good
Oct11Good
Nov10Good
Dec9Good
Location & terrain

Where is Ōyama?

Ōyama sits at 34.6°N, 138.2°E, 50 m above sea level, in Japan. The nearest listed city is Omaezaki, 1.0 km away.

Topography around Ōyama

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

Within 3 km, the terrain around Ōyama has only modest variations in elevation — a maximum elevation change of 51 m around an average of 8 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 154 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,311 m.

The land around Ōyama is covered by water (70%) within 3 km, water (80%) within 16 km, and water (55%) and trees (37%) within 80 km.

3 km
51 m
16 km
154 m
80 km
2,311 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Omaezaki 1.0 km · Sagara 9.0 km · Kikugawa 14 km · Maruobara 17 km · Sumiyoshi 17 km · Shimada 24 km · Kanaya 25 km · Kakegawa 26 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 Ōyama (34.6036°, 138.2172°, elevation 50 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).