Muikamachi weather in September

In September, Muikamachi sees average daytime highs of 22°C and overnight lows near 14°C, with 188 mm of rain across 16.3 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 24°C in the first days to 19°C by the end. The sky is clear or mostly clear about 15% of the time in September, and the air most often feels humid.

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 Muikamachi's 8th-clearest and 9th-windiest month. For the whole year in context, see Muikamachi's year-round climate.

Daytime high
22°
3rd warmest
Overnight low
14°
10th coldest
Rainfall
188 mm
16.3 wet days
Daylight
12 h 12 min
5:32 AM – 5:46 PM
Cloud cover
72%
8th clearest
Wind
6 km/h
9th windiest
Solar energy
3.84 kWh/m²
Travel score
5.3
out of 10

Muikamachi is dissolved municipality in Minamiuonuma district, Niigata prefecture, Japan.

Founded
1900

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 24°C in the first days to 19°C by the end.

A typical September day in Muikamachi reaches about 22°C in the afternoon and slips back to 14°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 18°C and 26°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°151015202530
Avg high (°C)Avg low (°C)
12417
22417
32417
42417
52417
62416
72316
82316
92316
102316
112316
122215
132215
142215
152215
162215
172114
182114
192114
202114
212013
222013
232013
242013
252012
261912
271912
281912
291912
301911

How September really feels in Muikamachi

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.

Muikamachi 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° / -7°21325.225.49.70.0
Feb / -6°16720.820.610.60.0
Mar / -4°16821.118.311.70.1
Apr11° / 13416.76.212.92.1
May17° / 14515.20.6144.8
Jun21° / 13°17917.3014.55.0
Jul24° / 17°24921.1014.35.0
Aug26° / 18°17718013.45.5
Sep22° / 14°18816.3012.35.3
Oct16° / 17716.30.5114.1
Nov / 14418.27.4101.5
Dec / -5°19022.920.19.50.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 15% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 70%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13565
23466
33466
43466
53466
63367
73367
83268
93169
103169
113169
123070
133070
143070
153070
162872
172872
182872
192872
202872
212872
222872
232773
242773
252773
262773
272773
282674
292674
302773

Chance of precipitation in September

Any precipitation

Muikamachi gets around 188 mm of rain over 16.3 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 56% and peaks near 58% on the wettest days.

0%20%40%60%151015202530
Rain chance (%)
158
257
357
457
557
657
757
857
956
1056
1156
1256
1355
1455
1555
1655
1754
1854
1954
2054
2154
2254
2354
2454
2555
2655
2755
2856
2956
3056

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 30% of days. Sticky, muggy-or-worse air turns up on roughly 13% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
141944311
242045301
352144291
462244271
572344261
682443250
792543230
8102642220
9112741200
10132840190
11142939170
12163038160
13193037140
14213136130
15233134110
16263232100
1729323190
1832322970
1935322760
2038312550
2141312350
2244302140
2348301930
2451291730
2554291520
2657281320
2759271220
2863261010
296525910
306724810

Wind in September

Winds average 6 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

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 5:19 AM to 5:44 AM, and sunset from 6:09 PM to 5:24 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:196:09
212.85:206:08
312.85:216:06
412.75:226:05
512.75:236:03
612.65:236:02
712.65:246:00
812.65:255:58
912.55:265:57
1012.55:275:55
1112.45:285:54
1212.45:285:52
1312.45:295:51
1412.35:305:49
1512.35:315:47
1612.25:325:46
1712.25:335:44
1812.25:335:43
1912.15:345:41
2012.15:355:39
2112.05:365:38
2212.05:375:36
2311.95:385:35
2411.95:395:33
2511.95:395:32
2611.85:405:30
2711.85:415:28
2811.75:425:27
2911.75:435:25
3011.75:445:24

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.84 kWh/m².

For context, solar energy here swings from a low near 2.07 kWh/m² to a high of 5.57 kWh/m² in May across the year — September's 3.84 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.3Bright
24.3Bright
34.2Bright
44.2Bright
54.2Bright
64.1Bright
74.1Bright
84.0Bright
94.0Bright
104.0Moderate
113.9Moderate
123.9Moderate
133.9Moderate
143.8Moderate
153.8Moderate
163.8Moderate
173.8Moderate
183.7Moderate
193.7Moderate
203.7Moderate
213.6Moderate
223.6Moderate
233.6Moderate
243.5Moderate
253.5Moderate
263.5Moderate
273.5Moderate
283.5Moderate
293.4Moderate
303.4Moderate
Planning a trip in September

Hazard calendar for Muikamachi

In seasonPeak

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

Muikamachi 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 Muikamachi?

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

5.3
Sightseeing
2nd-best month of the year
3.5
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Muikamachi for sightseeing.

What to pack for Muikamachi in September

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

In September, Muikamachi sees daytime highs around 22°C and nights near 14°C. Pack rain gear. About 16 days see rain.

rain gear

Sea temperature near Muikamachi 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 at the nearest coast (about 41 km away) 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 Muikamachi in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Muikamachi peaks around August 12 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 2 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 12UV 10Dec 21UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun9Very high
Jul10Very high
Aug10Very high
Sep8Very high
Oct5High
Nov3Moderate
Dec2Moderate

Air quality in Muikamachi 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 Muikamachi is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1821 µg/m³Dec 1610 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug13Moderate
Sep12Good
Oct12Good
Nov11Good
Dec10Good
Location & terrain

Where is Muikamachi?

Muikamachi sits at 37.1°N, 138.9°E, 162 m above sea level, in Japan. The nearest listed city is Minamiuonuma, 2.0 km away.

Topography around Muikamachi

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

Within 3 km, the terrain around Muikamachi has significant variations in elevation — a maximum elevation change of 461 m around an average of 231 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,862 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,551 m.

The land around Muikamachi is covered by trees (43%) and cropland (33%) within 3 km, trees (77%) within 16 km, and trees (75%) within 80 km.

3 km
461 m
16 km
1,862 m
80 km
2,551 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Minamiuonuma 2.0 km · Shiozawa 4.0 km · Tōkamachi 13 km · Uonuma 21 km · Ojiya 27 km · Nagaoka 43 km · Minakami 43 km · Kashiwazaki 45 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 Muikamachi (37.0667°, 138.8833°, elevation 162 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).