Minamata weather in September

In September, Minamata sees average daytime highs of 28°C and overnight lows near 21°C, with 181 mm of rain across 13.5 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 30°C in the first days to 27°C by the end. The sky is clear or mostly clear about 31% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 42 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Minamata's 4th-clearest and 12th-windiest month. For the whole year in context, see Minamata's year-round climate.

Daytime high
28°
3rd warmest
Overnight low
21°
10th coldest
Rainfall
181 mm
13.5 wet days
Daylight
12 h 12 min
6:07 AM – 6:19 PM
Cloud cover
61%
4th clearest
Wind
8 km/h
12th windiest
Solar energy
4.2 kWh/m²
Travel score
5.3
out of 10

Minamata is city in Kumamoto Prefecture, Japan.

Density
180/km²
people per km²
Founded
1949

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 30°C in the first days to 27°C by the end.

A typical September day in Minamata reaches about 28°C in the afternoon and slips back to 21°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 31°C. Set against its neighbours, September runs about 3°C cooler than August and about 5°C warmer than October.

15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13023
23023
33023
43023
53023
63023
73022
82922
92922
102922
112922
122922
132922
142921
152921
162821
172821
182821
192821
202820
212820
222820
232720
242720
252720
262719
272719
282719
292719
302619

How September really feels in Minamata

Once humidity and wind are folded in, September averages 7 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
7
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Minamata 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
Jan10° / 7810110.12.4
Feb12° / 9810.10.510.83.0
Mar15° / 14013.10.111.84.4
Apr20° / 11°16512012.85.8
May24° / 16°18912.2013.66.4
Jun26° / 20°48218.9014.14.9
Jul30° / 24°37019.4013.93.9
Aug31° / 24°17616.4013.23.8
Sep28° / 21°18113.5012.25.3
Oct24° / 15°1058.6011.27.2
Nov18° / 10°1038.9010.36.0
Dec13° / 878.90.49.93.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 52%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14456
24456
34555
44555
54555
64555
74555
84654
94654
104654
114753
124753
134753
144852
154852
164852
174951
184852
194951
204951
214951
224951
235050
244951
254951
265050
275050
285050
295149
305149

Chance of precipitation in September

Any precipitation

Minamata gets around 181 mm of rain over 13.5 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 44% and peaks near 53% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
153
253
352
452
551
651
750
849
949
1048
1147
1246
1345
1444
1543
1642
1742
1841
1941
2040
2140
2239
2339
2438
2538
2638
2737
2837
2937
3036

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 38% of days. Sticky, muggy-or-worse air turns up on roughly 71% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
100423649
200425638
300426637
401528597
501529596
601630576
702631565
802732545
912833524
1013934504
11131034483
12141234463
13251334443
14261534413
15261634402
16371833372
17382032352
18492132331
194102331311
205112430291
215122530271
225142629251
236152729231
246162828211
256172928191
267182927181
277203027161
288213026151
298223025140
309233024130

Wind in September

Winds average 8 km/h in September, the calmest month.

Across September, 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.

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 42 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 60 minutes over September. Sunrise moves from 5:57 AM to 6:16 AM, and sunset from 6:39 PM to 5:59 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:576:39
212.75:586:38
312.65:596:36
412.65:596:35
512.66:006:34
612.56:006:32
712.56:016:31
812.56:026:30
912.46:026:28
1012.46:036:27
1112.46:046:25
1212.36:046:24
1312.36:056:23
1412.36:066:21
1512.26:066:20
1612.26:076:19
1712.26:086:17
1812.16:086:16
1912.16:096:14
2012.16:096:13
2112.06:106:12
2212.06:116:10
2312.06:116:09
2411.96:126:07
2511.96:136:06
2611.96:136:05
2711.86:146:03
2811.86:156:02
2911.86:156:01
3011.76:165:59

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.2 kWh/m².

For context, solar energy here swings from a low near 2.36 kWh/m² to a high of 5.1 kWh/m² in May across the year — September's 4.2 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.4Bright
44.4Bright
54.4Bright
64.4Bright
74.4Bright
84.4Bright
94.3Bright
104.3Bright
114.3Bright
124.3Bright
134.3Bright
144.3Bright
154.3Bright
164.2Bright
174.2Bright
184.2Bright
194.2Bright
204.2Bright
214.1Bright
224.1Bright
234.1Bright
244.1Bright
254.1Bright
264.0Bright
274.0Bright
284.0Bright
294.0Moderate
304.0Moderate
Planning a trip in September

Hazard calendar for Minamata

In seasonPeak

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

Minamata sits in the Pacific typhoon belt; the season peaks July–October.

Minamata's rainy season runs June–July, when most of the year's rain falls.

Pacific typhoon
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Minamata?

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

5.3
Sightseeing
5th-best month of the year
6.3
Beach & pool
1st-best month of the year

September is a reasonable time to visit Minamata for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Minamata in September

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

In September, Minamata sees daytime highs around 28°C and nights near 21°C. Pack light clothes. Worth having: rain gear. About 14 days see rain.

light clothesrain gear

Sea temperature near Minamata in September

The nearest coast averages about 27°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 28°C and coldest in February near 16°C.

It's comfortable for a long swim from May 16 to Dec 4 — about 6.7 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan17Cool
Feb16Cool
Mar17Cool
Apr18Cool
May20Refreshing
Jun23Refreshing
Jul26Warm
Aug28Warm
Sep27Warm
Oct24Warm
Nov22Refreshing
Dec19Cool

UV index in Minamata in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Minamata peaks around July 12 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJul 12UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr8Very high
May8Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep10Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Minamata 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 Minamata is worst in March — around 24 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (July, 13 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 2424 µg/m³Jul 2114 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb20Moderate
Mar24Moderate
Apr24Moderate
May22Moderate
Jun18Moderate
Jul13Moderate
Aug14Moderate
Sep14Moderate
Oct14Moderate
Nov16Moderate
Dec15Moderate
Location & terrain

Where is Minamata?

Minamata sits at 32.2°N, 130.4°E, 2 m above sea level, in Japan. The nearest listed city is Sashiki, 14 km away.

Topography around Minamata

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

Within 3 km, the terrain around Minamata has significant variations in elevation — a maximum elevation change of 287 m around an average of 38 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 914 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,718 m.

The land around Minamata is covered by trees (41%) and water (37%) within 3 km, water (48%) and trees (46%) within 16 km, and trees (50%) and water (42%) within 80 km.

3 km
287 m
16 km
914 m
80 km
1,718 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Sashiki 14 km · Izumi 15 km · Isa 26 km · Ōkuchi-shinohara 27 km · Akune 29 km · Tsuruda 31 km · Hitoyoshi 33 km · Amakusa 33 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 Minamata (32.2167°, 130.4°, elevation 2 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).