Susaki weather in September

In September, Susaki sees average daytime highs of 27°C and overnight lows near 20°C, with 342 mm of rain across 18.3 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 25°C by the end. The sky is clear or mostly clear about 25% of the time in September, and the air most often feels muggy.

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

Daytime high
27°
3rd warmest
Overnight low
20°
10th coldest
Rainfall
342 mm
18.3 wet days
Daylight
12 h 12 min
5:55 AM – 6:07 PM
Cloud cover
65%
8th clearest
Wind
7 km/h
9th windiest
Solar energy
4.27 kWh/m²
Travel score
5.2
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 25°C by the end.

A typical September day in Susaki reaches about 27°C in the afternoon and slips back to 20°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 29°C. Set against its neighbours, September runs about 3°C cooler than August and about 5°C warmer than October.

10°15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12822
22822
32822
42821
52821
62821
72821
82821
92821
102721
112721
122720
132720
142720
152720
162720
172619
182619
192619
202619
212619
222619
232618
242518
252518
262518
272518
282517
292517
302517

How September really feels in Susaki

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.

Susaki 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 / 696.41.3101.9
Feb10° / 968.51.510.82.3
Mar14° / 159120.411.73.8
Apr18° / 20111.70.112.85.6
May22° / 14°24213.4013.76.1
Jun25° / 18°37219.7014.24.9
Jul29° / 22°38422.40144.0
Aug29° / 23°32522.4013.23.8
Sep27° / 20°34218.3012.25.2
Oct22° / 14°23011.4011.26.6
Nov17° / 1148.4010.35.5
Dec11° / 876.60.59.83.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 59%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13862
23961
33862
43862
53862
63862
73961
83961
93961
103961
114060
124159
134159
144258
154258
164159
174258
184159
194258
204159
214159
224258
234258
244258
254357
264357
274357
284357
294456
304456

Chance of precipitation in September

Any precipitation

Susaki gets around 342 mm of rain over 18.3 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 60% and peaks near 73% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
173
272
371
470
570
669
768
867
967
1066
1165
1264
1362
1461
1560
1659
1758
1857
1957
2056
2155
2254
2354
2453
2552
2652
2751
2851
2950
3049

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 33% 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 (%)
101830592
201831591
302932561
4021034531
5021135511
6031236481
7031337461
8031438431
9141539411
10151639381
11161740360
12171839340
13282039320
14292139290
153102238270
164112337250
174122436230
185132535210
196142634190
206152733180
217162832160
228172931140
239183030130
2410193029120
2510203128110
261121312790
271222322680
281323322580
291423322470
301624312360

Wind in September

Winds average 7 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
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

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 5:45 AM to 6:05 AM, and sunset from 6:28 PM to 5:47 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:456:28
212.75:456:27
312.75:466:26
412.65:476:24
512.65:486:23
612.65:486:21
712.55:496:20
812.55:506:19
912.55:506:17
1012.45:516:16
1112.45:526:14
1212.35:526:13
1312.35:536:12
1412.35:546:10
1512.25:546:09
1612.25:556:07
1712.25:566:06
1812.15:566:04
1912.15:576:03
2012.15:586:02
2112.05:596:00
2212.05:595:59
2312.06:005:57
2411.96:015:56
2511.96:015:54
2611.86:025:53
2711.86:035:52
2811.86:035:50
2911.76:045:49
3011.76:055:47

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.27 kWh/m².

For context, solar energy here swings from a low near 2.55 kWh/m² to a high of 5.53 kWh/m² in May across the year — September's 4.27 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.7Bright
44.6Bright
54.6Bright
64.6Bright
74.5Bright
84.5Bright
94.5Bright
104.5Bright
114.4Bright
124.4Bright
134.4Bright
144.3Bright
154.3Bright
164.3Bright
174.3Bright
184.2Bright
194.2Bright
204.2Bright
214.2Bright
224.1Bright
234.1Bright
244.1Bright
254.0Bright
264.0Bright
274.0Moderate
284.0Moderate
293.9Moderate
303.9Moderate
Planning a trip in September

Hazard calendar for Susaki

In seasonPeak

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

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

Susaki's rainy season runs April–October, 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 Susaki?

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

5.2
Sightseeing
5th-best month of the year
5.2
Beach & pool
1st-best month of the year

September is a reasonable time to visit Susaki for sightseeing.

What to pack for Susaki in September

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

In September, Susaki sees daytime highs around 27°C and nights near 20°C. Pack rain gear. Worth having: light clothes. About 18 days see rain.

rain gearlight clothes

Sea temperature near Susaki 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 17°C.

It's comfortable for a long swim from May 8 to Dec 15 — about 7.3 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan18Cool
Feb17Cool
Mar17Cool
Apr18Cool
May21Refreshing
Jun23Refreshing
Jul26Warm
Aug28Warm
Sep27Warm
Oct25Warm
Nov23Refreshing
Dec20Cool

UV index in Susaki 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 Susaki peaks around July 11 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 highModerateJul 11UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr7High
May9Very high
Jun10Extreme
Jul11Extreme
Aug10Very high
Sep10Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Susaki 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 Susaki is worst in April — around 22 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (October, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1321 µg/m³Oct 1311 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb16Moderate
Mar20Moderate
Apr22Moderate
May19Moderate
Jun16Moderate
Jul13Moderate
Aug12Moderate
Sep11Good
Oct11Good
Nov12Good
Dec11Good
Location & terrain

Where is Susaki?

Susaki sits at 33.4°N, 133.3°E, 6 m above sea level, in Japan. The nearest listed city is Tosa, 19 km away.

Topography around Susaki

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

Within 3 km, the terrain around Susaki has significant variations in elevation — a maximum elevation change of 327 m around an average of 50 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,002 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,894 m.

The land around Susaki is covered by trees (52%) and water (23%) within 3 km, trees (60%) and water (34%) within 16 km, and trees (61%) and water (34%) within 80 km.

3 km
327 m
16 km
1,002 m
80 km
1,894 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Tosa 19 km · Ino 22 km · Kochi 28 km · Shinagawa 38 km · Nankoku 38 km · Yamashita 43 km · Tosayamadachō-nakano 43 km · Nakamura 57 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 Susaki (33.3947°, 133.2913°, elevation 6 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).