Sanjō weather in May

In May, Sanjō sees average daytime highs of 22°C and overnight lows near 11°C, with 116 mm of rain across 13.1 wet days and about 14 hours of daylight. It is the 5th-warmest and 11th-wettest month of the year here.

Highs climb over the month, from about 20°C in the first days to 24°C by the end. The sky is clear or mostly clear about 28% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 30 min at the start of May to 14 h 24 min by month's end. Set against the rest of the year, May is Sanjō's 4th-clearest and 7th-windiest month. For the whole year in context, see Sanjō's year-round climate.

Daytime high
22°
5th warmest
Overnight low
11°
8th coldest
Rainfall
116 mm
13.1 wet days
Daylight
14 hours
4:40 AM – 6:41 PM
Cloud cover
65%
4th clearest
Wind
7 km/h
7th windiest
Solar energy
5.54 kWh/m²
Travel score
6.1
out of 10

Sanjō is city in Niigata Prefecture, Japan.

Density
219/km²
people per km²
Founded
1934

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 20°C in the first days to 24°C by the end.

A typical May day in Sanjō reaches about 22°C in the afternoon and slips back to 11°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 27°C. Set against its neighbours, May runs about 6°C warmer than April and about 4°C cooler than June.

10°20°30°151015202531
Avg high (°C)Avg low (°C)
1208
2209
3209
4209
5209
6209
72110
82110
92110
102110
112110
122111
132111
142111
152211
162211
172211
182212
192212
202212
212212
222312
232312
242313
252313
262313
272313
282313
292413
302414
312414

How May really feels in Sanjō

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.

Sanjō weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -2°20525.720.79.70.0
Feb / -2°14921.517.210.50.1
Mar / 15020.810.611.71.3
Apr16° / 11615.31.312.94.3
May22° / 11°11613.10146.1
Jun25° / 16°14314.1014.55.8
Jul28° / 21°24417.7014.34.6
Aug30° / 22°16915.7013.44.3
Sep26° / 17°15615.1012.35.6
Oct20° / 11°15715.80115.4
Nov13° / 15318.51.3103.0
Dec / -0°2022412.89.40.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% 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 60%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14258
24258
34159
44159
54159
64159
74159
84060
94060
104060
114060
124060
133961
144060
154060
164060
174060
184060
194060
204060
214060
224060
234060
244060
254159
264159
274060
284060
294159
304060
314060

Chance of precipitation in May

Any precipitation

Sanjō gets around 116 mm of rain over 13.1 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 42% and peaks near 44% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
144
243
343
443
543
643
743
843
943
1044
1144
1244
1344
1444
1544
1644
1744
1843
1943
2042
2142
2241
2341
2440
2540
2639
2739
2838
2938
3038
3137

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 76% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
192710
291810
390910
490910
5891010
6871120
7861220
8851320
9841420
10831520
11821620
12821620
13801730
14791830
15791830
16781930
17781930
18762040
19762040
20742150
21732250
22712360
23702460
24682570
25672670
26642880
27622990
285931100
295633110
305335120
315037131

Wind in May

Winds average 7 km/h in May.

Across May, 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
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 30 min at the start of May to 14 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 54 minutes over May. Sunrise moves from 4:55 AM to 4:30 AM, and sunset from 6:27 PM to 6:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.54:556:27
213.64:546:28
313.64:536:29
413.64:526:30
513.74:516:31
613.74:506:32
713.74:496:33
813.84:486:34
913.84:466:35
1013.84:456:36
1113.94:446:37
1213.94:446:37
1313.94:436:38
1414.04:426:39
1514.04:416:40
1614.04:406:41
1714.04:396:42
1814.14:386:43
1914.14:376:44
2014.14:376:44
2114.24:366:45
2214.24:356:46
2314.24:356:47
2414.24:346:48
2514.34:336:49
2614.34:336:49
2714.34:326:50
2814.34:326:51
2914.34:316:52
3014.44:316:52
3114.44:306:53

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.54 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 1.7 kWh/m² to a high of 5.54 kWh/m² in May across the year — May's 5.54 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.4Bright
25.4Bright
35.4Bright
45.4Bright
55.4Bright
65.4Bright
75.4Bright
85.4Bright
95.4Bright
105.4Bright
115.4Bright
125.5Bright
135.5Bright
145.5Bright
155.5Bright
165.5Bright
175.5Bright
185.6Bright
195.6Bright
205.6Bright
215.6Bright
225.7Bright
235.7Bright
245.7Bright
255.7Bright
265.7Bright
275.8Bright
285.8Bright
295.8Bright
305.8Bright
315.8Bright
Planning a trip in May

Hazard calendar for Sanjō

In seasonPeak

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

Sanjō 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 Sanjō?

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

6.1
Sightseeing
1st-best month of the year
4.1
Beach & pool
5th-best month of the year

May is a reasonable time to visit Sanjō for sightseeing.

What to pack for Sanjō in May

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

In May, Sanjō sees daytime highs around 22°C and nights near 11°C. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

Sea temperature near Sanjō in May

The nearest coast averages about 15°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 29 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 21 to Oct 31 — about 4.4 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan12Bracing
Feb11Bracing
Mar10Bracing
Apr11Bracing
May15Bracing
Jun19Cool
Jul23Refreshing
Aug26Warm
Sep25Warm
Oct22Refreshing
Nov18Cool
Dec15Cool

UV index in Sanjō in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sanjō peaks around August 12 at about 10 (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 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 12UV 10Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun8Very high
Jul9Very high
Aug10Very high
Sep8Very high
Oct5High
Nov3Moderate
Dec2Low

Air quality in Sanjō 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 Sanjō is worst in April — around 23 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1723 µg/m³Dec 1610 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb15Moderate
Mar22Moderate
Apr23Moderate
May22Moderate
Jun19Moderate
Jul17Moderate
Aug14Moderate
Sep12Moderate
Oct12Good
Nov11Good
Dec10Good
Location & terrain

Where is Sanjō?

Sanjō sits at 37.6°N, 138.9°E, 9 m above sea level, in Japan. The nearest listed city is Tsubame, 6.0 km away.

Topography around Sanjō

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

Within 3 km, the terrain around Sanjō has only modest variations in elevation — a maximum elevation change of 117 m around an average of 12 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 626 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,314 m.

The land around Sanjō is covered by artificial surfaces (45%) and cropland (40%) within 3 km, cropland (43%) and trees (38%) within 16 km, and trees (52%) and water (36%) within 80 km.

3 km
117 m
16 km
626 m
80 km
2,314 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Tsubame 6.0 km · Kamo 9.0 km · Mitsuke 9.0 km · Yoshida-kasugachō 9.0 km · Maki 16 km · Tochio-honchō 16 km · Shirone 18 km · Nagaoka 21 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 Sanjō (37.6167°, 138.95°, elevation 9 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).