Saiki weather in September

In September, Saiki sees average daytime highs of 27°C and overnight lows near 23°C, with 215 mm of rain across 13.6 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 2nd-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 34% 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 Saiki's 9th-clearest and 8th-windiest month. For the whole year in context, see Saiki's year-round climate.

Daytime high
27°
3rd warmest
Overnight low
23°
10th coldest
Rainfall
215 mm
13.6 wet days
Daylight
12 h 12 min
6:01 AM – 6:13 PM
Cloud cover
59%
9th clearest
Wind
14 km/h
8th windiest
Solar energy
4.4 kWh/m²
Travel score
6.0
out of 10

Saiki is city in Ōita Prefecture, Japan.

Density
74/km²
people per km²
Founded
2005

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 28°C in the first days to 25°C by the end.

A typical September day in Saiki reaches about 27°C in the afternoon and slips back to 23°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 29°C. Set against its neighbours, September runs about 3°C cooler than August and about 4°C warmer than October.

15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12825
22825
32825
42824
52824
62824
72824
82824
92824
102724
112724
122724
132723
142723
152723
162723
172723
182623
192623
202622
212622
222622
232622
242622
252522
262521
272521
282521
292521
302521

How September really feels in Saiki

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.

Saiki weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan11° / 626.710.12.8
Feb11° / 717.910.83.0
Mar14° / 11010.611.74.2
Apr18° / 13°12910.312.85.9
May22° / 17°15110.413.76.5
Jun25° / 21°29715.514.15.6
Jul28° / 25°19814.1145.2
Aug29° / 26°16614.713.24.8
Sep27° / 23°21513.612.26.0
Oct22° / 18°161911.27.1
Nov18° / 13°907.710.36.1
Dec13° / 6879.94.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% 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 50%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14852
24753
34753
44753
54753
64852
74852
84852
94951
104951
114951
124951
134951
144951
154951
165050
175050
185050
195050
205149
215149
225149
235248
245248
255248
265248
275347
285347
295347
305347

Chance of precipitation in September

Any precipitation

Saiki gets around 215 mm of rain over 13.6 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 45% and peaks near 50% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
150
250
350
449
549
649
749
848
948
1047
1147
1246
1346
1445
1545
1644
1744
1844
1943
2043
2142
2242
2341
2441
2540
2640
2740
2839
2939
3039

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 36% of days. Sticky, muggy-or-worse air turns up on roughly 77% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1002174536
2002184634
3003194631
4003204729
5004214727
6014224725
7015244723
8016254721
9017254720
10018264618
11029274517
121210284415
131212284214
141313294113
151415293912
161416303711
172518303610
18261930349
19272131328
20282231307
21382331296
22392431276
233102531255
243112731244
253122731234
263132931213
274142930203
284162929193
294173029182
304183128172

Wind in September

Winds average 14 km/h in September.

Across September, daily wind ranges from about 13 km/h on the calmest days to 15 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
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1715light breeze
1815light breeze
1915light breeze
2015light breeze
2115light breeze
2215light breeze
2315light breeze
2415light breeze
2515light breeze
2615light breeze
2715light breeze
2815light breeze
2915light breeze
3015light breeze

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 5:51 AM to 6:10 AM, and sunset from 6:34 PM to 5:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:516:34
212.75:516:32
312.65:526:31
412.65:536:29
512.65:536:28
612.55:546:27
712.55:556:25
812.55:556:24
912.45:566:23
1012.45:576:21
1112.45:576:20
1212.35:586:18
1312.35:596:17
1412.35:596:16
1512.26:006:14
1612.26:016:13
1712.26:016:11
1812.16:026:10
1912.16:036:08
2012.16:036:07
2112.06:046:06
2212.06:056:04
2312.06:056:03
2411.96:066:01
2511.96:076:00
2611.96:085:59
2711.86:085:57
2811.86:095:56
2911.76:105:54
3011.76:105:53

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.4 kWh/m².

For context, solar energy here swings from a low near 2.52 kWh/m² to a high of 5.54 kWh/m² in May across the year — September's 4.4 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.8Bright
44.8Bright
54.8Bright
64.7Bright
74.7Bright
84.7Bright
94.6Bright
104.6Bright
114.6Bright
124.5Bright
134.5Bright
144.5Bright
154.5Bright
164.4Bright
174.4Bright
184.4Bright
194.3Bright
204.3Bright
214.3Bright
224.3Bright
234.2Bright
244.2Bright
254.2Bright
264.1Bright
274.1Bright
284.1Bright
294.1Bright
304.0Bright
Planning a trip in September

Hazard calendar for Saiki

In seasonPeak

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

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

Saiki's rainy season runs May–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 Saiki?

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

6.0
Sightseeing
4th-best month of the year
6.0
Beach & pool
3rd-best month of the year

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

What to pack for Saiki in September

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

In September, Saiki sees daytime highs around 27°C and nights near 23°C. Worth packing: light clothes and rain gear. About 14 days see rain.

light clothesrain gear

Sea temperature near Saiki 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 23 km away) is warmest in August at about 27°C and coldest in February near 17°C.

It's comfortable for a long swim from May 11 to Dec 14 — about 7.2 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan18Cool
Feb17Cool
Mar17Cool
Apr18Cool
May20Refreshing
Jun23Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Warm
Nov22Refreshing
Dec20Cool

UV index in Saiki 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 Saiki peaks around June 22 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 highModerateJun 22UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr8Very high
May8Very high
Jun11Extreme
Jul10Extreme
Aug10Very high
Sep10Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Saiki 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 Saiki is worst in April — around 23 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodGoodApr 1523 µg/m³Oct 1611 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb17Moderate
Mar22Moderate
Apr23Moderate
May22Moderate
Jun19Moderate
Jul16Moderate
Aug16Moderate
Sep12Moderate
Oct11Good
Nov12Moderate
Dec12Good
Location & terrain

Where is Saiki?

Saiki sits at 33.0°N, 131.9°E, 3 m above sea level, in Japan. The nearest listed city is Tsukumiura, 14 km away.

Topography around Saiki

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

Within 3 km, the terrain around Saiki has significant variations in elevation — a maximum elevation change of 300 m around an average of 44 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 716 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,758 m.

The land around Saiki is covered by trees (47%) and artificial surfaces (27%) within 3 km, trees (64%) and water (30%) within 16 km, and water (50%) and trees (45%) within 80 km.

3 km
300 m
16 km
716 m
80 km
1,758 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Tsukumiura 14 km · Usuki 21 km · Mie 30 km · Tsurusaki 38 km · Ōita 42 km · Nobeoka 46 km · Takedamachi 47 km · Beppu 52 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 Saiki (32.95°, 131.9°, elevation 3 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).