Setouchi weather in September

In September, Setouchi sees average daytime highs of 26°C and overnight lows near 22°C, with 181 mm of rain across 11.6 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 24°C by the end. The sky is clear or mostly clear about 35% 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 Setouchi's 7th-clearest and 8th-windiest month. For the whole year in context, see Setouchi's year-round climate.

Daytime high
26°
3rd warmest
Overnight low
22°
10th coldest
Rainfall
181 mm
11.6 wet days
Daylight
12 h 12 min
5:51 AM – 6:04 PM
Cloud cover
59%
7th clearest
Wind
13 km/h
8th windiest
Solar energy
4.42 kWh/m²
Travel score
6.4
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 24°C by the end.

A typical September day in Setouchi reaches about 26°C in the afternoon and slips back to 22°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 28°C. Set against its neighbours, September runs about 3°C cooler than August and about 5°C warmer than October.

15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12824
22824
32824
42824
52824
62723
72723
82723
92723
102723
112723
122723
132722
142622
152622
162622
172622
182622
192621
202621
212521
222521
232521
242521
252520
262520
272420
282420
292420
302419

How September really feels in Setouchi

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.

Setouchi weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 476.50.49.91.9
Feb / 597.60.610.72.1
Mar12° / 10810.1011.73.3
Apr16° / 11°12710.4012.85.1
May20° / 15°14210.2013.86.3
Jun23° / 20°18512.2014.36.1
Jul27° / 24°19212.7014.15.9
Aug29° / 25°10910.1013.35.6
Sep26° / 22°18111.6012.26.4
Oct22° / 17°1338.5011.16.9
Nov16° / 11°687010.25.6
Dec11° / 576.50.19.73.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% 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 50%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15149
25149
35149
45248
55149
65149
75149
85050
95149
105149
115050
125050
135050
145050
155050
164951
174951
184852
194951
204852
215050
224951
235050
244951
255050
265050
275149
285149
295149
305149

Chance of precipitation in September

Any precipitation

Setouchi gets around 181 mm of rain over 11.6 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 38% and peaks near 42% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
141
242
342
442
542
642
742
842
942
1041
1141
1240
1339
1439
1538
1637
1736
1836
1936
2035
2135
2235
2335
2435
2535
2635
2735
2835
2935
3035

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 29% of days. Sticky, muggy-or-worse air turns up on roughly 62% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1019264420
20110274419
30111284317
40112294216
50213304115
60214314013
70315323812
81316323711
91417333610
10141833349
11151934338
12262034317
13272134306
14282234295
15392333275
163112432254
174122532234
184132631223
195152731203
206162830183
216172929172
227183028162
238193027142
248203126132
259223125121
2610233224111
2711243223101
281224322291
291325322181
301426322071

Wind in September

Winds average 13 km/h in September.

Across September, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1413light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze

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 5:40 AM to 6:02 AM, and sunset from 6:26 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:406:26
212.75:416:25
312.75:426:23
412.75:426:22
512.65:436:20
612.65:446:19
712.55:456:17
812.55:456:16
912.55:466:15
1012.45:476:13
1112.45:486:12
1212.45:486:10
1312.35:496:09
1412.35:506:07
1512.35:516:06
1612.25:516:04
1712.25:526:03
1812.15:536:01
1912.15:546:00
2012.15:545:58
2112.05:555:57
2212.05:565:55
2312.05:575:54
2411.95:575:52
2511.95:585:51
2611.85:595:49
2711.86:005:48
2811.86:005:46
2911.76:015:45
3011.76:025:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.42 kWh/m².

For context, solar energy here swings from a low near 2.42 kWh/m² to a high of 5.76 kWh/m² in May across the year — September's 4.42 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
15.0Bright
24.9Bright
34.9Bright
44.8Bright
54.8Bright
64.8Bright
74.7Bright
84.7Bright
94.7Bright
104.6Bright
114.6Bright
124.6Bright
134.5Bright
144.5Bright
154.5Bright
164.4Bright
174.4Bright
184.3Bright
194.3Bright
204.3Bright
214.3Bright
224.2Bright
234.2Bright
244.2Bright
254.1Bright
264.1Bright
274.1Bright
284.0Bright
294.0Bright
304.0Bright
Planning a trip in September

Hazard calendar for Setouchi

In seasonPeak

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

Setouchi 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 Setouchi?

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

6.4
Sightseeing
2nd-best month of the year
6.2
Beach & pool
2nd-best month of the year

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

What to pack for Setouchi in September

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

In September, Setouchi sees daytime highs around 26°C and nights near 22°C. Worth packing: light clothes and rain gear. About 12 days see rain.

light clothesrain gear

Sea temperature near Setouchi in September

The nearest coast averages about 26°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 22 km away) is warmest in August at about 27°C and coldest in February near 13°C.

It's comfortable for a long swim from Jun 7 to Nov 12 — about 5.2 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan14Bracing
Feb13Bracing
Mar13Bracing
Apr15Bracing
May17Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Refreshing
Nov20Cool
Dec16Cool

UV index in Setouchi 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 Setouchi peaks around July 13 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 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 highVery highModerateJul 13UV 10Dec 22UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May8Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Setouchi 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 Setouchi is worst in April — around 23 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (October, 12 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1422 µg/m³Oct 1613 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb17Moderate
Mar21Moderate
Apr23Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug15Moderate
Sep13Moderate
Oct12Moderate
Nov13Moderate
Dec13Moderate
Location & terrain

Where is Setouchi?

Setouchi sits at 34.7°N, 134.1°E, 8 m above sea level, in Japan. The nearest listed city is Bizen, 17 km away.

Topography around Setouchi

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

Within 3 km, the terrain around Setouchi has only modest variations in elevation — a maximum elevation change of 245 m around an average of 46 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 511 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,522 m.

The land around Setouchi is covered by trees (65%) within 3 km, water (41%) and trees (38%) within 16 km, and trees (59%) and water (26%) within 80 km.

3 km
245 m
16 km
511 m
80 km
1,522 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Bizen 17 km · Okayama 19 km · Akaiwa 20 km · Tamano 24 km · Kariya 25 km · Naoshima 26 km · Kamigōri 31 km · Aioi 34 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 Setouchi (34.6592°, 134.1424°, elevation 8 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).