Ashibetsu weather in September

In September, Ashibetsu sees average daytime highs of 20°C and overnight lows near 11°C, with 144 mm of rain across 14.4 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 22°C in the first days to 17°C by the end. The sky is clear or mostly clear about 19% of the time in September, and the air most often feels dry.

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 Ashibetsu's 4th-clearest and 9th-windiest month. For the whole year in context, see Ashibetsu's year-round climate.

Daytime high
20°
3rd warmest
Overnight low
11°
9th coldest
Rainfall
144 mm
14.4 wet days
Daylight
12 h 18 min
5:17 AM – 5:34 PM
Cloud cover
68%
4th clearest
Wind
7 km/h
9th windiest
Solar energy
3.51 kWh/m²
Travel score
5.4
out of 10

Ashibetsu is city in Hokkaidō, Japan.

Density
22/km²
people per km²
Founded
1953

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 17°C by the end.

A typical September day in Ashibetsu reaches about 20°C in the afternoon and slips back to 11°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 16°C and 23°C. Set against its neighbours, September runs about 4°C cooler than August and about 7°C warmer than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12215
22215
32214
42214
52214
62214
72214
82113
92113
102113
112113
122112
132012
142012
152012
162011
171911
181911
191910
201910
211910
221810
23189
24189
25189
26189
27179
28178
29178
30178

How September really feels in Ashibetsu

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.

Ashibetsu 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-5° / -12°6716.220.59.10.0
Feb-3° / -11°5614.317.910.20.0
Mar / -7°7515.616.611.60.0
Apr / 8014.17.413.21.6
May16° / 9413.30.614.54.4
Jun19° / 12°8812.4015.25.6
Jul23° / 16°14214.8014.95.9
Aug24° / 17°17614.8013.85.9
Sep20° / 11°14414.4012.35.4
Oct13° / 11915.71.510.83.2
Nov / -3°11318.713.49.50.4
Dec-2° / -9°9218.722.18.80.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 19% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 19% of September, with mostly cloudy or overcast conditions the remaining 62%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13367
23367
33367
43367
53367
63466
73466
83565
93565
103565
113664
123763
133763
143862
153862
163961
173961
183961
194060
204060
214258
224258
234258
244159
254258
264258
274159
284258
294258
304258

Chance of precipitation in September

Any precipitation

Ashibetsu gets around 144 mm of rain over 14.4 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 48% and peaks near 49% on the wettest days.

0%20%40%60%151015202530
Rain chance (%)
149
249
349
448
548
648
748
848
948
1048
1148
1247
1347
1447
1547
1647
1747
1847
1947
2047
2147
2248
2348
2448
2548
2649
2749
2849
2949
3049

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 58% of days. Sticky, muggy-or-worse air turns up on roughly 5% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
123342814
224352713
326362613
428362412
530362311
632362210
734362010
83735199
94035178
104234167
114533157
124832136
135231125
145430115
155828104
16612694
17642583
18672373
19712162
20732052
21751852
22771742
23811531
24821431
25841321
26851221
27881110
28891010
2990910
3091810

Wind in September

Winds average 7 km/h in September.

Across September, daily wind ranges from about 7 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

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 5:00 AM to 5:33 AM, and sunset from 6:02 PM to 5:08 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:006:02
213.05:016:01
312.95:025:59
412.95:035:57
512.85:045:55
612.85:055:53
712.75:065:51
812.75:085:49
912.65:095:48
1012.65:105:46
1112.55:115:44
1212.55:125:42
1312.45:135:40
1412.45:145:38
1512.35:165:36
1612.35:175:34
1712.25:185:32
1812.25:195:31
1912.15:205:29
2012.15:215:27
2112.05:235:25
2212.05:245:23
2311.95:255:21
2411.95:265:19
2511.85:275:17
2611.85:285:15
2711.75:305:14
2811.75:315:12
2911.65:325:10
3011.65:335:08

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.51 kWh/m².

For context, solar energy here swings from a low near 1.6 kWh/m² to a high of 5.25 kWh/m² in May across the year — September's 3.51 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.8Moderate
23.8Moderate
33.8Moderate
43.8Moderate
53.8Moderate
63.7Moderate
73.7Moderate
83.7Moderate
93.6Moderate
103.6Moderate
113.6Moderate
123.6Moderate
133.6Moderate
143.5Moderate
153.5Moderate
163.5Moderate
173.5Moderate
183.4Moderate
193.4Moderate
203.4Moderate
213.4Moderate
223.4Moderate
233.3Moderate
243.3Moderate
253.3Moderate
263.3Moderate
273.2Moderate
283.2Moderate
293.2Moderate
303.1Moderate
Planning a trip in September

Is September a good time to visit Ashibetsu?

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

5.4
Sightseeing
4th-best month of the year
2.7
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Ashibetsu for sightseeing.

What to pack for Ashibetsu in September

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

In September, Ashibetsu sees daytime highs around 20°C and nights near 11°C. Pack rain gear. About 14 days see rain.

rain gear

Sea temperature near Ashibetsu in September

The nearest coast averages about 21°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 61 km away) is warmest in August at about 21°C and coldest in February near 5°C.

It's comfortable for a long swim from Aug 3 to Sep 20 — about 1.6 months when the water holds above 20°C.

10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarm
Sea temperature (°C)Comfort
Jan6Bracing
Feb5Bracing
Mar5Bracing
Apr7Bracing
May10Bracing
Jun14Bracing
Jul18Cool
Aug21Refreshing
Sep21Refreshing
Oct17Cool
Nov13Bracing
Dec9Bracing

UV index in Ashibetsu 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 Ashibetsu peaks around August 17 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighHighVery highHighModerateLowAug 17UV 8Dec 20UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar3Moderate
Apr5High
May7Very high
Jun7High
Jul6High
Aug8Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Ashibetsu 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 Ashibetsu is worst in April — around 17 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1517 µg/m³Dec 178 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb11Good
Mar16Moderate
Apr17Moderate
May15Moderate
Jun11Good
Jul11Good
Aug9Good
Sep8Good
Oct9Good
Nov9Good
Dec7Good
Location & terrain

Where is Ashibetsu?

Ashibetsu sits at 43.5°N, 142.2°E, 111 m above sea level, in Japan. The nearest listed city is Sunagawa, 23 km away.

Topography around Ashibetsu

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

Within 3 km, the terrain around Ashibetsu has significant variations in elevation — a maximum elevation change of 328 m around an average of 154 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 883 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,253 m.

The land around Ashibetsu is covered by trees (71%) within 3 km, trees (90%) within 16 km, and trees (73%) within 80 km.

3 km
328 m
16 km
883 m
80 km
2,253 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Sunagawa 23 km · Takikawa 23 km · Shimo-furano 24 km · Furano 24 km · Fukagawa 25 km · Asahikawa 32 km · Bibai 33 km · Iwamizawa 49 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 Ashibetsu (43.5097°, 142.1856°, elevation 111 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. 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).