Aki in Fall

In fall (September, October and November), Aki sees average daytime highs around 22°C and overnight lows near 16°C, with 637 mm of rain over about 36 wet days across the season. It is the 2nd-warmest season and the 2nd-wettest season.

Over the season highs ease from about 27°C in early September to 15°C by late November. The sky is clear or mostly clear about 40% of the time across fall, and the air most often feels dry.

Fall is Aki's best season of the year to visit on our travel score. For the whole year in context, see Aki's year-round climate.

Avg daytime high
22°C
2nd-warmest season
Avg overnight low
16°C
Rainfall
637 mm
36 wet days
Avg wind
10 km/h
Travel score
6.0
best season of the year
Months
Sep · Oct · Nov

Temperature in Aki in Fall

Average highAverage lowShaded bands: 10–90% of days

Over the season highs ease from about 27°C in early September to 15°C by late November.

A typical fall day in Aki reaches about 22°C and drops to 16°C overnight. The warmest of the three months is September, the coolest November.

10°20°30°SepOctNov

How fall really feels in Aki

Once humidity and wind are folded in, fall brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

fall sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Aki weather by month

How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 776.40.5102.3
Feb10° / 1017.80.910.82.5
Mar13° / 16711.20.111.73.8
Apr18° / 11°20311.6012.85.4
May21° / 16°23612.7013.76.0
Jun24° / 20°35819.1014.25.1
Jul27° / 23°35320.30144.7
Aug28° / 24°26119.6013.24.6
Sep26° / 21°30216.9012.25.5
Oct22° / 16°21711.3011.26.6
Nov17° / 11°1188.1010.35.8
Dec12° / 876.109.83.6

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 40% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitation

Aki gets around 637 mm of rain over 36 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%SepOctNov

Wind in Fall

Winds average 10 km/h across fall.

051015SepOctNov

Sunrise & sunset in Fall

DaylightNight

Daylight runs from about 12 h 42 min in early September to 10 hours by late November. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMSepOctNov

Solar energy in Fall

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across fall, about 3.7 kWh/m².

024SepOctNov
Planning a trip in fall

Hazard calendar for Aki

In seasonPeak

In fall, Aki overlaps its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.

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

Aki's rainy season runs March–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 fall a good time to visit Aki?

Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

6.0
Sightseeing
1st-best month of the year
3.7
Beach & pool
2nd-best month of the year

fall is a reasonable time to visit Aki for sightseeing.

What to pack for Aki in Fall

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

In fall, Aki sees daytime highs around 22°C and nights near 16°C. Pack rain gear. Worth having: light clothes and a warm layer. About 36 days see rain.

rain gearlight clothesa warm layer

Sea temperature near Aki in Fall

The nearest coast averages about 25°C across fall — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 14 km away) is warmest in August at about 28°C and coldest in February near 17°C.

It's comfortable for a long swim from May 3 to Dec 19 — about 7.6 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan18Cool
Feb17Cool
Mar18Cool
Apr19Cool
May21Refreshing
Jun23Refreshing
Jul26Warm
Aug28Warm
Sep27Warm
Oct25Warm
Nov23Refreshing
Dec20Refreshing

UV index in Aki in Fall

LowModerateHighVery highExtreme

Clear-sky midday UV across fall averages around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Aki peaks around June 23 at about 11 (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 — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJun 23UV 11Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr8Very high
May9Very high
Jun11Extreme
Jul11Extreme
Aug9Very high
Sep10Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Aki in Fall

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.

Air quality in Aki is worst in April — around 20 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (September, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1320 µg/m³Sep 2010 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar19Moderate
Apr20Moderate
May18Moderate
Jun15Moderate
Jul11Good
Aug11Good
Sep10Good
Oct10Good
Nov11Good
Dec11Good
Location & terrain

Where is Aki?

Aki sits at 33.5°N, 133.9°E, 13 m above sea level, in Japan. The nearest listed city is Yamashita, 20 km away.

Topography around Aki

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

Within 3 km, the terrain around Aki has significant variations in elevation — a maximum elevation change of 426 m around an average of 37 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,031 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,939 m.

The land around Aki is covered by water (45%) and trees (23%) within 3 km, trees (53%) and water (42%) within 16 km, and trees (54%) and water (41%) within 80 km.

3 km
426 m
16 km
1,031 m
80 km
1,939 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Fall weather nearby: Yamashita 20 km · Tosayamadachō-nakano 23 km · Nankoku 24 km · Muroto-misakicho 34 km · Kochi 34 km · Tosa 42 km · Ino 44 km · Susaki 58 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 Aki (33.5°, 133.9°, elevation 13 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.