Katsuura in Fall
In fall (September, October and November), Katsuura sees average daytime highs around 21°C and overnight lows near 17°C, with 535 mm of rain over about 40 wet days across the season. It is the 2nd-warmest season and the wettest season of the year.
Over the season highs ease from about 28°C in early September to 15°C by late November. The sky is clear or mostly clear about 30% of the time across fall, and the air most often feels dry.
Fall is Katsuura's best season of the year to visit on our travel score. For the whole year in context, see Katsuura's year-round climate.
- Avg daytime high
- 21°C
- 2nd-warmest season
- Avg overnight low
- 17°C
- Rainfall
- 535 mm
- 40 wet days
- Avg wind
- 13 km/h
- Travel score
- 5.6
- best season of the year
- Months
- Sep · Oct · Nov
Temperature in Katsuura in Fall
Over the season highs ease from about 28°C in early September to 15°C by late November.
A typical fall day in Katsuura reaches about 21°C and drops to 17°C overnight. The warmest of the three months is September, the coolest November.
How fall really feels in Katsuura
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.
fall sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Katsuura 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.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 10° / 5° | 91 | 8.6 | 0.6 | 9.9 | 2.3 |
| Feb | 10° / 5° | 87 | 9.4 | 0.8 | 10.7 | 2.3 |
| Mar | 13° / 8° | 144 | 13.6 | 0.3 | 11.7 | 3.2 |
| Apr | 17° / 12° | 117 | 11.9 | 0 | 12.9 | 5.0 |
| May | 21° / 16° | 131 | 11.8 | 0 | 13.8 | 6.0 |
| Jun | 24° / 20° | 179 | 13.9 | 0 | 14.3 | 5.8 |
| Jul | 28° / 24° | 139 | 13 | 0 | 14.1 | 5.6 |
| Aug | 29° / 25° | 112 | 12.6 | 0 | 13.3 | 5.2 |
| Sep | 26° / 22° | 185 | 14.9 | 0 | 12.2 | 5.7 |
| Oct | 21° / 17° | 223 | 13.6 | 0 | 11.1 | 6.0 |
| Nov | 17° / 13° | 127 | 11.4 | 0 | 10.2 | 5.2 |
| Dec | 12° / 8° | 85 | 9.8 | 0 | 9.7 | 3.5 |
Cloud cover in Fall
The sky is clear or mostly clear about 30% of the time across fall.
Chance of precipitation in Fall
Katsuura gets around 535 mm of rain over 40 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 13 km/h across fall.
Sunrise & sunset in Fall
Daylight runs from about 12 h 48 min in early September to 9 h 48 min by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.2 kWh/m².
Hazard calendar for Katsuura
In fall, Katsuura overlaps its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Katsuura sits in the Pacific typhoon belt; the season peaks July–October.
Is fall a good time to visit Katsuura?
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.
fall is a reasonable time to visit Katsuura for sightseeing.
What to pack for Katsuura in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, Katsuura sees daytime highs around 21°C and nights near 17°C. Pack rain gear. Worth having: light clothes and a warm layer. About 40 days see rain.
Sea temperature near Katsuura in Fall
The nearest coast averages about 24°C across fall — 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 26°C and coldest in February near 16°C.
It's comfortable for a long swim from May 22 to Dec 9 — about 6.6 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 18 | 16 | 16 | 18 | 20 | 22 | 24 | 26 | 26 | 24 | 22 | 20 |
| Comfort | Cool | Cool | Cool | Cool | Cool | Refreshing | Refreshing | Warm | Warm | Refreshing | Refreshing | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 18 | Cool |
| Feb | 16 | Cool |
| Mar | 16 | Cool |
| Apr | 18 | Cool |
| May | 20 | Cool |
| Jun | 22 | Refreshing |
| Jul | 24 | Refreshing |
| Aug | 26 | Warm |
| Sep | 26 | Warm |
| Oct | 24 | Refreshing |
| Nov | 22 | Refreshing |
| Dec | 20 | Cool |
UV index in Katsuura in Fall
Clear-sky midday UV across fall averages around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Katsuura peaks around August 11 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 3 | 4 | 5 | 7 | 9 | 9 | 10 | 10 | 8 | 6 | 4 | 2 |
| Level | Moderate | Moderate | Moderate | High | Very high | Very high | Extreme | Extreme | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 4 | Moderate |
| Mar | 5 | Moderate |
| Apr | 7 | High |
| May | 9 | Very high |
| Jun | 9 | Very high |
| Jul | 10 | Extreme |
| Aug | 10 | Extreme |
| Sep | 8 | Very high |
| Oct | 6 | High |
| Nov | 4 | Moderate |
| Dec | 2 | Moderate |
Air quality in Katsuura in Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.
Air quality in Katsuura is worst in April — around 22 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (September, 11 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 14 | 17 | 21 | 22 | 21 | 16 | 12 | 11 | 11 | 14 | 14 | 13 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 14 | Moderate |
| Feb | 17 | Moderate |
| Mar | 21 | Moderate |
| Apr | 22 | Moderate |
| May | 21 | Moderate |
| Jun | 16 | Moderate |
| Jul | 12 | Good |
| Aug | 11 | Good |
| Sep | 11 | Good |
| Oct | 14 | Moderate |
| Nov | 14 | Moderate |
| Dec | 13 | Moderate |
Where is Katsuura?
Katsuura sits at 35.1°N, 140.3°E, 23 m above sea level, in Japan. The nearest listed city is Isumi, 12 km away.
Topography around Katsuura
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Katsuura.
Within 3 km, the terrain around Katsuura has only modest variations in elevation — a maximum elevation change of 162 m around an average of 30 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 379 m; within 80 km, significant variations in elevation — a maximum elevation change of 394 m.
The land around Katsuura is covered by water (56%) and trees (35%) within 3 km, water (59%) and trees (34%) within 16 km, and water (59%) and trees (21%) within 80 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
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 Katsuura (35.1462°, 140.3151°, elevation 23 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.