Ōmamachō-ōmama weather in September

In September, Ōmamachō-ōmama sees average daytime highs of 24°C and overnight lows near 17°C, with 204 mm of rain across 17.2 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 26°C in the first days to 21°C by the end. The sky is clear or mostly clear about 20% 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 Ōmamachō-ōmama's 9th-clearest and 10th-windiest month. For the whole year in context, see Ōmamachō-ōmama's year-round climate.

Daytime high
24°
3rd warmest
Overnight low
17°
10th coldest
Rainfall
204 mm
17.2 wet days
Daylight
12 h 12 min
5:30 AM – 5:44 PM
Cloud cover
70%
9th clearest
Wind
5 km/h
10th windiest
Solar energy
3.64 kWh/m²
Travel score
5.4
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 26°C in the first days to 21°C by the end.

A typical September day in Ōmamachō-ōmama reaches about 24°C in the afternoon and slips back to 17°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 20°C and 28°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12620
22620
32620
42619
52619
62619
72519
82519
92519
102519
112518
122518
132418
142418
152418
162417
172417
182317
192317
202316
212316
222316
232216
242216
252215
262215
272215
282115
292115
302114

How September really feels in Ōmamachō-ōmama

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.

Ōmamachō-ōmama 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 / -2°517.25.59.80.1
Feb / -2°518.35.910.60.4
Mar10° / 9912.45.411.72.0
Apr15° / 11412.71.312.94.4
May20° / 11°13614.3013.95.6
Jun23° / 16°17318.4014.45.1
Jul27° / 20°21721.3014.24.7
Aug28° / 21°17420.2013.44.7
Sep24° / 17°20417.2012.25.4
Oct18° / 11°16813.4011.15.4
Nov13° / 667.80.310.13.9
Dec / 4573.39.61.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 66%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13466
23565
33466
43367
53367
63268
73367
83268
93268
103268
113268
123268
133268
143268
153268
163268
173268
183367
193367
203367
213466
223466
233565
243565
253565
263664
273763
283763
293862
303961

Chance of precipitation in September

Any precipitation

Ōmamachō-ōmama gets around 204 mm of rain over 17.2 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 58% and peaks near 63% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
163
263
363
463
562
662
761
861
961
1060
1160
1259
1359
1458
1558
1658
1757
1857
1957
2056
2156
2255
2355
2454
2554
2654
2753
2853
2953
3053

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 30% of days. Sticky, muggy-or-worse air turns up on roughly 32% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
117305012
218314911
318324810
42933479
521033469
631034458
731134438
841335427
951435407
1061535386
1171635366
1281835345
1391935325
14102134304
15122234284
16132433273
17152532253
18172631233
19182831212
20202930192
21223129172
22243228151
23263327131
24283425121
25303524101
2632362391
2733372271
2835382060
2937381950
3039391840

Wind in September

Winds average 5 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 5 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

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 5:18 AM to 5:42 AM, and sunset from 6:07 PM to 5:22 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:186:07
212.85:196:06
312.75:206:04
412.75:216:03
512.75:216:01
612.65:226:00
712.65:235:58
812.55:245:56
912.55:255:55
1012.55:265:53
1112.45:265:52
1212.45:275:50
1312.35:285:49
1412.35:295:47
1512.35:305:46
1612.25:305:44
1712.25:315:43
1812.15:325:41
1912.15:335:39
2012.15:345:38
2112.05:345:36
2212.05:355:35
2312.05:365:33
2411.95:375:32
2511.95:385:30
2611.85:395:29
2711.85:395:27
2811.85:405:25
2911.75:415:24
3011.75:425:22

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.64 kWh/m².

For context, solar energy here swings from a low near 2.33 kWh/m² to a high of 5.29 kWh/m² in May across the year — September's 3.64 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.0Bright
24.0Bright
34.0Moderate
43.9Moderate
53.9Moderate
63.9Moderate
73.9Moderate
83.8Moderate
93.8Moderate
103.8Moderate
113.7Moderate
123.7Moderate
133.7Moderate
143.6Moderate
153.6Moderate
163.6Moderate
173.5Moderate
183.5Moderate
193.5Moderate
203.5Moderate
213.5Moderate
223.4Moderate
233.4Moderate
243.4Moderate
253.4Moderate
263.3Moderate
273.3Moderate
283.3Moderate
293.3Moderate
303.3Moderate
Planning a trip in September

Hazard calendar for Ōmamachō-ōmama

In seasonPeak

In September, Ōmamachō-ōmama sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Ōmamachō-ōmama's rainy season runs March–October, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Ōmamachō-ōmama?

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

5.4
Sightseeing
2nd-best month of the year
4.4
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Ōmamachō-ōmama for sightseeing.

What to pack for Ōmamachō-ōmama in September

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

In September, Ōmamachō-ōmama sees daytime highs around 24°C and nights near 17°C. Pack rain gear. Worth having: light clothes. About 17 days see rain.

rain gearlight clothes

UV index in Ōmamachō-ōmama 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 Ōmamachō-ōmama peaks around July 16 at about 9 (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 highModerateJul 16UV 9Dec 23UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun9Very high
Jul10Very high
Aug9Very high
Sep8Very high
Oct6High
Nov3Moderate
Dec2Moderate

Air quality in Ōmamachō-ōmama 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 Ōmamachō-ōmama is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1721 µg/m³Dec 179 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun16Moderate
Jul14Moderate
Aug13Moderate
Sep11Good
Oct11Good
Nov10Good
Dec9Good
Location & terrain

Where is Ōmamachō-ōmama?

Ōmamachō-ōmama sits at 36.4°N, 139.3°E, 182 m above sea level, in Japan. The nearest listed city is Midori, 2.0 km away.

Topography around Ōmamachō-ōmama

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

Within 3 km, the terrain around Ōmamachō-ōmama has significant variations in elevation — a maximum elevation change of 321 m around an average of 210 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,779 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,552 m.

The land around Ōmamachō-ōmama is covered by artificial surfaces (42%) and trees (41%) within 3 km, trees (56%) and artificial surfaces (25%) within 16 km, and trees (67%) within 80 km.

3 km
321 m
16 km
1,779 m
80 km
2,552 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Midori 2.0 km · Kiryū 6.0 km · Isesaki 14 km · Ōta 17 km · Maebashi 18 km · Sakai-nakajima 18 km · Ashikaga 19 km · Tamamura 20 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 Ōmamachō-ōmama (36.4318°, 139.2753°, elevation 182 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. 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).