Asahikawa weather in September

In September, Asahikawa sees average daytime highs of 20°C and overnight lows near 12°C, with 143 mm of rain across 14.4 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 23°C in the first days to 18°C by the end. The sky is clear or mostly clear about 20% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Asahikawa's 3rd-clearest and 9th-windiest month. For the whole year in context, see Asahikawa's year-round climate.

Daytime high
20°
3rd warmest
Overnight low
12°
9th coldest
Rainfall
143 mm
14.4 wet days
Daylight
12 h 18 min
5:16 AM – 5:34 PM
Cloud cover
67%
3rd clearest
Wind
8 km/h
9th windiest
Solar energy
3.55 kWh/m²
Travel score
5.6
out of 10

Asahikawa is city in Hokkaido, Japan.

Density
446/km²
people per km²
Founded
1877

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 23°C in the first days to 18°C by the end.

A typical September day in Asahikawa reaches about 20°C in the afternoon and slips back to 12°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 24°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)
12315
22315
32315
42314
52314
62214
72214
82214
92213
102213
112113
122113
132112
142112
152112
162012
172011
182011
192011
202010
211910
221910
231910
24199
25199
26189
27189
28189
29188
30178

How September really feels in Asahikawa

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.

Asahikawa weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-4° / -12°571520.49.10.0
Feb-2° / -11°501317.110.20.0
Mar / -6°6714.915.711.60.0
Apr10° / 7713.65.813.22.1
May16° / 91130.414.54.8
Jun20° / 12°9012.4015.25.8
Jul24° / 16°14714.4014.96.0
Aug24° / 17°17115013.85.9
Sep20° / 12°14314.4012.35.6
Oct14° / 11515.61.210.83.5
Nov / -2°10718.412.39.50.5
Dec-1° / -9°8317.321.78.80.0

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 19% of September, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
13565
23565
33664
43664
53664
63664
73664
83763
93763
103763
113763
123763
133961
143961
153862
163961
173961
184060
194060
204159
214159
224159
234159
244258
254357
264258
274357
284357
294357
304258

Chance of precipitation in September

Any precipitation

Asahikawa gets around 143 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 50% on the wettest days.

0%20%40%60%151015202530
Rain chance (%)
148
249
349
449
549
649
749
849
948
1048
1148
1248
1348
1447
1547
1647
1747
1847
1947
2047
2147
2247
2348
2448
2548
2649
2749
2849
2950
3050

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 56% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1213230161
2223329151
3243428140
4263427130
5283525120
6303523120
7323522110
8353520100
937351990
1040341780
1143341680
1246331470
1349321360
1451311260
1555301050
165928940
176127840
186525730
196724630
207022530
217320520
227618420
237817320
248016310
258314210
268413210
278512210
288811100
298910100
30909100

Wind in September

Winds average 8 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.

051015151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min 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 90 minutes over September. Sunrise moves from 4:59 AM to 5:33 AM, and sunset from 6:02 PM to 5:07 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.14:596:02
213.05:006:00
313.05:015:58
412.95:025:56
512.95:035:55
612.85:045:53
712.85:055:51
812.75:075:49
912.75:085:47
1012.65:095:45
1112.65:105:43
1212.55:115:41
1312.55:125:39
1412.45:145:38
1512.35:155:36
1612.35:165:34
1712.25:175:32
1812.25:185:30
1912.15:195:28
2012.15:215:26
2112.05:225:24
2212.05:235:22
2311.95:245:20
2411.95:255:18
2511.85:275:17
2611.85:285:15
2711.75:295:13
2811.75:305:11
2911.65:315:09
3011.65:335:07

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.55 kWh/m².

For context, solar energy here swings from a low near 1.53 kWh/m² to a high of 5.25 kWh/m² in May across the year — September's 3.55 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.9Moderate
23.9Moderate
33.9Moderate
43.8Moderate
53.8Moderate
63.8Moderate
73.8Moderate
83.7Moderate
93.7Moderate
103.7Moderate
113.6Moderate
123.6Moderate
133.6Moderate
143.6Moderate
153.5Moderate
163.5Moderate
173.5Moderate
183.5Moderate
193.5Moderate
203.4Moderate
213.4Moderate
223.4Moderate
233.4Moderate
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 Asahikawa?

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

5.6
Sightseeing
4th-best month of the year
3.1
Beach & pool
4th-best month of the year

September is a reasonable time to visit Asahikawa for sightseeing.

What to pack for Asahikawa in September

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

In September, Asahikawa sees daytime highs around 20°C and nights near 12°C. Pack rain gear. About 14 days see rain.

rain gear

Sea temperature near Asahikawa 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 60 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 Asahikawa 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 Asahikawa peaks around August 16 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 1 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighVery highHighModerateLowAug 16UV 8Dec 21UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar3Moderate
Apr6High
May7Very high
Jun7Very high
Jul6High
Aug9Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Asahikawa 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 Asahikawa 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 Asahikawa?

Asahikawa sits at 43.8°N, 142.4°E, 121 m above sea level, in Japan. The nearest listed city is Fukagawa, 27 km away.

Topography around Asahikawa

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

Within 3 km, the terrain around Asahikawa has only modest variations in elevation — a maximum elevation change of 64 m around an average of 115 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 755 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,253 m.

The land around Asahikawa is covered by artificial surfaces (77%) within 3 km, trees (51%) and cropland (31%) within 16 km, and trees (81%) within 80 km.

3 km
64 m
16 km
755 m
80 km
2,253 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Fukagawa 27 km · Ashibetsu 32 km · Minamishibetsuchō 43 km · Takikawa 44 km · Furano 47 km · Shimo-furano 47 km · Sunagawa 49 km · Rumoi 61 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 Asahikawa (43.7706°, 142.3649°, elevation 121 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).