Kashiwazaki weather in September

In September, Kashiwazaki sees average daytime highs of 26°C and overnight lows near 19°C, with 163 mm of rain across 14.9 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 29°C in the first days to 24°C by the end. The sky is clear or mostly clear about 20% of the time in September, and the air most often feels muggy.

Daylight stretches from about 12 h 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Kashiwazaki's 6th-clearest and 9th-windiest month. For the whole year in context, see Kashiwazaki's year-round climate.

Daytime high
26°
3rd warmest
Overnight low
19°
10th coldest
Rainfall
163 mm
14.9 wet days
Daylight
12 h 12 min
5:33 AM – 5:47 PM
Cloud cover
68%
6th clearest
Wind
6 km/h
9th windiest
Solar energy
4.02 kWh/m²
Travel score
5.6
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 29°C in the first days to 24°C by the end.

A typical September day in Kashiwazaki reaches about 26°C in the afternoon and slips back to 19°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 22°C and 31°C. Set against its neighbours, September runs about 4°C cooler than August and about 6°C warmer than October.

10°15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12921
22921
32921
42821
52821
62821
72820
82820
92820
102720
112720
122719
132719
142719
152619
162619
172618
182618
192518
202518
212517
222517
232517
242417
252417
262416
272416
282416
292316
302316

How September really feels in Kashiwazaki

Once humidity and wind are folded in, September 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

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

Kashiwazaki weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°21525.618.99.70.0
Feb / -1°15621.115.710.60.2
Mar10° / 143208.811.71.7
Apr16° / 10414.50.812.94.6
May22° / 12°10412.90146.2
Jun25° / 17°12613.5014.55.9
Jul29° / 22°21216.9014.34.5
Aug31° / 23°14514.5013.44.2
Sep26° / 19°16314.9012.35.6
Oct20° / 12°16015.40115.6
Nov14° / 15918.20.7103.3
Dec / 20823.710.59.50.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14159
24159
34159
44159
54258
64159
74159
84159
94159
104159
114159
124159
133961
144060
154060
163862
173961
183862
193763
203763
213664
223664
233664
243664
253664
263565
273466
283565
293565
303565

Chance of precipitation in September

Any precipitation

Kashiwazaki gets around 163 mm of rain over 14.9 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 51% and peaks near 53% on the wettest days.

0%20%40%60%151015202530
Rain chance (%)
150
251
351
451
552
652
752
852
953
1053
1153
1253
1352
1452
1551
1651
1750
1850
1949
2049
2149
2249
2349
2449
2549
2649
2749
2849
2950
3050

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the muggy band about 32% of days. Sticky, muggy-or-worse air turns up on roughly 49% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1021443392
2021544372
3031644362
4031744341
5041844321
6042044301
7152144281
8162243261
9172443251
10182543231
11292642211
122102741191
133122840180
144132938160
155143037140
166163135130
177173133110
188193232100
19920323080
201022332870
211223332660
221325332450
231426332240
241528342040
251729341830
261830331630
271931331420
282033331220
292233321120
302334311010

Wind in September

Winds average 6 km/h in September.

Across September, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 48 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 66 minutes over September. Sunrise moves from 5:20 AM to 5:45 AM, and sunset from 6:11 PM to 5:25 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:206:11
212.85:216:09
312.85:226:08
412.75:236:06
512.75:246:05
612.65:256:03
712.65:256:02
812.65:266:00
912.55:275:58
1012.55:285:57
1112.45:295:55
1212.45:305:54
1312.45:305:52
1412.35:315:50
1512.35:325:49
1612.25:335:47
1712.25:345:46
1812.25:355:44
1912.15:365:42
2012.15:365:41
2112.05:375:39
2212.05:385:38
2311.95:395:36
2411.95:405:34
2511.95:415:33
2611.85:425:31
2711.85:435:30
2811.75:435:28
2911.75:445:27
3011.75:455:25

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.02 kWh/m².

For context, solar energy here swings from a low near 1.89 kWh/m² to a high of 5.75 kWh/m² in May across the year — September's 4.02 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.5Bright
44.4Bright
54.4Bright
64.3Bright
74.3Bright
84.3Bright
94.2Bright
104.2Bright
114.1Bright
124.1Bright
134.1Bright
144.0Bright
154.0Moderate
164.0Moderate
173.9Moderate
183.9Moderate
193.9Moderate
203.8Moderate
213.8Moderate
223.8Moderate
233.8Moderate
243.7Moderate
253.7Moderate
263.7Moderate
273.6Moderate
283.6Moderate
293.6Moderate
303.5Moderate
Planning a trip in September

Hazard calendar for Kashiwazaki

In seasonPeak

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

Kashiwazaki 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 September a good time to visit Kashiwazaki?

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

5.6
Sightseeing
3rd-best month of the year
5.5
Beach & pool
4th-best month of the year

September is a reasonable time to visit Kashiwazaki for sightseeing.

What to pack for Kashiwazaki in September

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

In September, Kashiwazaki sees daytime highs around 26°C and nights near 19°C. Pack rain gear. Worth having: light clothes. About 15 days see rain.

rain gearlight clothes

Sea temperature near Kashiwazaki in September

The nearest coast averages about 25°C in September — 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 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
Jun20Cool
Jul23Refreshing
Aug27Warm
Sep25Warm
Oct22Refreshing
Nov18Cool
Dec15Cool

UV index in Kashiwazaki in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Kashiwazaki peaks around August 12 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 12UV 10Jan 1UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug10Very high
Sep9Very high
Oct5High
Nov3Moderate
Dec2Moderate

Air quality in Kashiwazaki in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Kashiwazaki 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 Kashiwazaki?

Kashiwazaki sits at 37.4°N, 138.6°E, 4 m above sea level, in Japan. The nearest listed city is Ojiya, 23 km away.

Topography around Kashiwazaki

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

Within 3 km, the terrain around Kashiwazaki has only modest variations in elevation — a maximum elevation change of 148 m around an average of 14 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 974 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,405 m.

The land around Kashiwazaki is covered by artificial surfaces (36%) and water (33%) within 3 km, trees (48%) and water (40%) within 16 km, and trees (52%) and water (36%) within 80 km.

3 km
148 m
16 km
974 m
80 km
2,405 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Ojiya 23 km · Nagaoka 28 km · Tōkamachi 32 km · Jōetsu 37 km · Mitsuke 39 km · Uonuma 39 km · Tochio-honchō 41 km · Minamiuonuma 43 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 Kashiwazaki (37.3667°, 138.55°, elevation 4 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).