Aizu-Wakamatsu weather in September

In September, Aizu-Wakamatsu sees average daytime highs of 23°C and overnight lows near 16°C, with 144 mm of rain across 13 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 2nd-wettest month of the year here.

Highs ease over the month, from about 25°C in the first days to 20°C by the end. The sky is clear or mostly clear about 16% of the time in September, and the air most often feels humid.

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 Aizu-Wakamatsu's 7th-clearest and 9th-windiest month. For the whole year in context, see Aizu-Wakamatsu's year-round climate.

Daytime high
23°
3rd warmest
Overnight low
16°
10th coldest
Rainfall
144 mm
13 wet days
Daylight
12 h 12 min
5:27 AM – 5:42 PM
Cloud cover
71%
7th clearest
Wind
7 km/h
9th windiest
Solar energy
3.56 kWh/m²
Travel score
6.0
out of 10

Aizu-Wakamatsu is city in Fukushima prefecture, Japan.

Density
309/km²
people per km²
Founded
1955

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 25°C in the first days to 20°C by the end.

A typical September day in Aizu-Wakamatsu reaches about 23°C in the afternoon and slips back to 16°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 27°C. Set against its neighbours, September runs about 4°C cooler than August and about 6°C warmer than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12619
22619
32519
42519
52518
62518
72518
82518
92418
102418
112417
122417
132417
142417
152317
162316
172316
182316
192216
202215
212215
222215
232115
242114
252114
262114
272114
282014
292013
302013

How September really feels in Aizu-Wakamatsu

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.

Aizu-Wakamatsu 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 daysSnow daysDaylight (hours)Travel score
Jan / -4°10018.919.89.70.0
Feb / -4°7315.315.410.60.0
Mar / -1°10115.610.611.70.7
Apr13° / 9512.82.412.93.5
May19° / 9511.80145.8
Jun23° / 15°11712.5014.56.0
Jul26° / 19°18017014.35.4
Aug27° / 20°13213.9013.45.7
Sep23° / 16°14413012.36.0
Oct17° / 10°12511.70115.1
Nov11° / 8213.22.6102.5
Dec / -1°9318.113.59.50.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 16% 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 68%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13565
23466
33466
43466
53466
63466
73466
83466
93466
103367
113367
123268
133367
143367
153367
163268
173268
183268
193268
203070
213070
223169
233169
243169
253169
263169
273268
283169
293268
303268

Chance of precipitation in September

Any precipitation

Aizu-Wakamatsu gets around 144 mm of rain over 13 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 44% and peaks near 47% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
147
247
347
447
547
647
747
847
946
1046
1146
1246
1345
1445
1545
1644
1744
1843
1943
2042
2142
2242
2341
2441
2541
2641
2741
2841
2941
3040

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 29% of days. Sticky, muggy-or-worse air turns up on roughly 28% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1110324512
2110334411
3211344410
421135439
531235429
631335418
741435397
851635387
951735366
1061835355
1181935335
1292135324
13102234304
14122333283
15132533263
16152632242
17172831222
18192930202
19213129191
20233227171
21253326151
22273425131
23303623110
24313722100
2533372180
2635381970
2737391860
2840391650
2942391540
3044391430

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
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
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 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 5:15 AM to 5:40 AM, and sunset from 6:05 PM to 5:19 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:156:05
212.85:156:04
312.85:166:02
412.75:176:01
512.75:185:59
612.65:195:58
712.65:205:56
812.65:215:54
912.55:215:53
1012.55:225:51
1112.45:235:50
1212.45:245:48
1312.45:255:46
1412.35:265:45
1512.35:275:43
1612.25:275:42
1712.25:285:40
1812.25:295:38
1912.15:305:37
2012.15:315:35
2112.05:325:34
2212.05:335:32
2311.95:345:30
2411.95:345:29
2511.95:355:27
2611.85:365:26
2711.85:375:24
2811.75:385:22
2911.75:395:21
3011.75:405:19

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.56 kWh/m².

For context, solar energy here swings from a low near 2.02 kWh/m² to a high of 5.33 kWh/m² in May across the year — September's 3.56 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
14.0Moderate
24.0Moderate
33.9Moderate
43.9Moderate
53.9Moderate
63.8Moderate
73.8Moderate
83.8Moderate
93.7Moderate
103.7Moderate
113.7Moderate
123.6Moderate
133.6Moderate
143.6Moderate
153.5Moderate
163.5Moderate
173.5Moderate
183.5Moderate
193.4Moderate
203.4Moderate
213.4Moderate
223.4Moderate
233.3Moderate
243.3Moderate
253.3Moderate
263.3Moderate
273.2Moderate
283.2Moderate
293.2Moderate
303.2Moderate
Planning a trip in September

Hazard calendar for Aizu-Wakamatsu

In seasonPeak

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

Aizu-Wakamatsu 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 Aizu-Wakamatsu?

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

6.0
Sightseeing
1st-best month of the year
4.6
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Aizu-Wakamatsu for sightseeing.

What to pack for Aizu-Wakamatsu in September

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

In September, Aizu-Wakamatsu sees daytime highs around 23°C and nights near 16°C. Worth packing: light clothes and rain gear. About 13 days see rain.

light clothesrain gear

UV index in Aizu-Wakamatsu in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Aizu-Wakamatsu peaks around August 12 at about 10 (very high) — 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 12UV 10Dec 23UV 2
UV index (midday)Level
Jan2Moderate
Feb3Moderate
Mar5Moderate
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug10Very high
Sep8Very high
Oct6High
Nov3Moderate
Dec2Low

Air quality in Aizu-Wakamatsu 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 Aizu-Wakamatsu is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1721 µg/m³Dec 1810 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar20Moderate
Apr21Moderate
May20Moderate
Jun16Moderate
Jul14Moderate
Aug12Good
Sep11Good
Oct12Good
Nov11Good
Dec10Good
Location & terrain

Where is Aizu-Wakamatsu?

Aizu-Wakamatsu sits at 37.5°N, 139.9°E, 238 m above sea level, in Japan. The nearest listed city is Bange, 14 km away.

Topography around Aizu-Wakamatsu

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

Within 3 km, the terrain around Aizu-Wakamatsu has significant variations in elevation — a maximum elevation change of 539 m around an average of 322 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,422 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,125 m.

The land around Aizu-Wakamatsu is covered by trees (49%) and artificial surfaces (45%) within 3 km, trees (53%) and cropland (27%) within 16 km, and trees (85%) within 80 km.

3 km
539 m
16 km
1,422 m
80 km
2,125 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Bange 14 km · Aizu-misato Machi 15 km · Kitakata 19 km · Kōriyama 40 km · Motomiya 40 km · Kumakura 43 km · Nihommatsu 44 km · Sukagawa 45 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 Aizu-Wakamatsu (37.4914°, 139.9455°, elevation 238 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). 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).