Mutsu weather in September

In September, Mutsu sees average daytime highs of 21°C and overnight lows near 19°C, with 151 mm of rain across 12.3 wet days and about 12.3 hours of daylight. It is the 2nd-warmest and 2nd-wettest month of the year here.

Highs ease over the month, from about 22°C in the first days to 19°C by the end. The sky is clear or mostly clear about 28% of the time in September, and the air most often feels humid.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Mutsu's 6th-clearest and 8th-windiest month. For the whole year in context, see Mutsu's year-round climate.

Daytime high
21°
2nd warmest
Overnight low
19°
11th coldest
Rainfall
151 mm
12.3 wet days
Daylight
12 h 18 min
5:21 AM – 5:38 PM
Cloud cover
63%
6th clearest
Wind
23 km/h
8th windiest
Solar energy
3.96 kWh/m²
Travel score
5.9
out of 10

Mutsu is city in Aomori Prefecture, Japan.

Density
65/km²
people per km²
Founded
1959

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 22°C in the first days to 19°C by the end.

A typical September day in Mutsu reaches about 21°C in the afternoon and slips back to 19°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 18°C and 23°C. Set against its neighbours, September runs about 2°C cooler than August and about 5°C warmer than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
12220
22220
32220
42220
52220
62220
72220
82220
92220
102120
112120
122119
132119
142119
152119
162119
172119
182119
192018
202018
212018
222018
232018
242018
252018
261917
271917
281917
291917
301917

How September really feels in Mutsu

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.

Mutsu weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -2°10018.416.89.40.0
Feb / -2°71141410.30.0
Mar / 7112.2811.70.0
Apr / 7410.21.513.10.7
May11° / 9910.8014.32.7
Jun15° / 13°909.3014.94.6
Jul19° / 18°14011.7014.75.8
Aug22° / 20°15311.3013.76.4
Sep21° / 19°15112.3012.35.9
Oct15° / 13°11312.4010.94.5
Nov / 8613.21.69.71.5
Dec / 11016.411.29.10.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14060
24060
33961
43961
54060
64060
74060
84060
94159
103961
113961
124060
134060
144060
154159
164159
174159
184159
194159
204258
214258
224357
234357
244456
254456
264456
274555
284555
294654
304654

Chance of precipitation in September

Any precipitation

Mutsu gets around 151 mm of rain over 12.3 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 42% and peaks near 42% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
141
241
341
441
541
641
741
842
942
1042
1142
1242
1342
1442
1542
1642
1742
1842
1941
2041
2141
2241
2341
2441
2541
2642
2742
2842
2942
3042

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 23% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1314323714
2315333514
3315343413
4416343312
5417353212
6518353011
7620352911
8721352710
982235269
1092335249
11112435238
12122534217
13142534207
14162633186
15192733175
16212832155
17232831134
18252930124
19283030103
2030302893
2132302783
2234302672
2336312562
2438312452
2540312341
2642312241
2744312131
2846311931
2949311820
3051301720

Wind in September

Winds average 23 km/h in September.

Across September, daily wind ranges from about 21 km/h on the calmest days to 25 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202530
Wind speed (km/h)Feels
121breezy
221breezy
321breezy
421breezy
521breezy
621breezy
721breezy
821breezy
922breezy
1022breezy
1122breezy
1222breezy
1322breezy
1422breezy
1522breezy
1622breezy
1723breezy
1823breezy
1923breezy
2023breezy
2123breezy
2224breezy
2324breezy
2424breezy
2524breezy
2624breezy
2725breezy
2825breezy
2925breezy
3025breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over September. Sunrise moves from 5:06 AM to 5:36 AM, and sunset from 6:04 PM to 5:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:066:04
212.95:076:02
312.95:086:00
412.85:095:59
512.85:105:57
612.75:115:55
712.75:125:54
812.65:135:52
912.65:145:50
1012.65:155:48
1112.55:165:47
1212.55:175:45
1312.45:185:43
1412.45:195:41
1512.35:205:39
1612.35:215:38
1712.25:225:36
1812.25:235:34
1912.15:245:32
2012.15:255:30
2112.05:275:29
2212.05:285:27
2311.95:295:25
2411.95:305:23
2511.85:315:22
2611.85:325:20
2711.85:335:18
2811.75:345:16
2911.75:355:15
3011.65:365:13

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.96 kWh/m².

For context, solar energy here swings from a low near 1.73 kWh/m² to a high of 5.67 kWh/m² in May across the year — September's 3.96 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.3Bright
24.3Bright
34.2Bright
44.2Bright
54.2Bright
64.1Bright
74.1Bright
84.1Bright
94.1Bright
104.0Bright
114.0Bright
124.0Bright
134.0Moderate
144.0Moderate
153.9Moderate
163.9Moderate
173.9Moderate
183.9Moderate
193.9Moderate
203.8Moderate
213.8Moderate
223.8Moderate
233.8Moderate
243.7Moderate
253.7Moderate
263.7Moderate
273.6Moderate
283.6Moderate
293.6Moderate
303.6Moderate
Planning a trip in September

Hazard calendar for Mutsu

In seasonPeak

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

Mutsu 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 Mutsu?

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

5.9
Sightseeing
2nd-best month of the year
3.4
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Mutsu for sightseeing.

What to pack for Mutsu in September

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

In September, Mutsu sees daytime highs around 21°C and nights near 19°C. Worth packing: rain gear and a windbreaker. About 12 days see rain.

rain geara windbreaker

Sea temperature near Mutsu in September

The nearest coast averages about 22°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 22°C and coldest in March near 7°C.

It's comfortable for a long swim from Jul 31 to Oct 3 — about 2.1 months when the water holds above 20°C.

5°10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan10Bracing
Feb7Bracing
Mar7Bracing
Apr8Bracing
May11Bracing
Jun14Bracing
Jul18Cool
Aug22Refreshing
Sep22Refreshing
Oct19Cool
Nov15Cool
Dec12Bracing

UV index in Mutsu in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks 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 Mutsu peaks around August 19 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 11 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighVery highHighModerateLowAug 19UV 8Jan 11UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr6High
May8Very high
Jun7Very high
Jul5Moderate
Aug8Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Mutsu 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 Mutsu is worst in April — around 19 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (December, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1419 µg/m³Dec 177 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb12Good
Mar17Moderate
Apr19Moderate
May16Moderate
Jun11Good
Jul10Good
Aug10Good
Sep9Good
Oct9Good
Nov8Good
Dec7Good
Location & terrain

Where is Mutsu?

Mutsu sits at 41.3°N, 141.2°E, 6 m above sea level, in Japan. The nearest listed city is Toyota, 60 km away.

Topography around Mutsu

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

Within 3 km, the terrain around Mutsu has only modest variations in elevation — a maximum elevation change of 63 m around an average of 14 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 868 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,559 m.

The land around Mutsu is covered by trees (38%) and artificial surfaces (27%) within 3 km, trees (59%) and water (33%) within 16 km, and water (63%) and trees (31%) within 80 km.

3 km
63 m
16 km
868 m
80 km
1,559 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Toyota 60 km · Aomori 66 km · Hakodate 67 km · Misawa 69 km · Towada 74 km · Hitokawame 75 km · Kamiiso 76 km · Hokuto 76 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 Mutsu (41.2894°, 141.2169°, 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).