Aso weather in April

In April, Aso sees average daytime highs of 18°C and overnight lows near 8°C, with 158 mm of precipitation across 11.7 wet days and about 12.8 hours of daylight. It is the 7th-warmest and 6th-wettest month of the year here.

Highs climb over the month, from about 16°C in the first days to 20°C by the end. The sky is clear or mostly clear about 30% of the time in April, and the air most often feels dry.

Daylight stretches from about 12 h 18 min at the start of April to 13 h 18 min by month's end. Set against the rest of the year, April is Aso's 5th-clearest and 3rd-windiest month. For the whole year in context, see Aso's year-round climate.

Daytime high
18°
7th warmest
Overnight low
6th coldest
Precipitation
158 mm
11.7 wet days
Daylight
12 h 48 min
5:51 AM – 6:40 PM
Cloud cover
62%
5th clearest
Wind
8 km/h
3rd windiest
Solar energy
4.94 kWh/m²
Travel score
5.5
out of 10

Aso is city in Kumamoto Prefecture, Japan.

Density
72/km²
people per km²
Founded
2005

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 16°C in the first days to 20°C by the end.

A typical April day in Aso reaches about 18°C in the afternoon and slips back to 8°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 14°C and 23°C. Set against its neighbours, April runs about 5°C warmer than March and about 4°C cooler than May.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
1166
2166
3166
4166
5176
6177
7177
8177
9177
10187
11187
12188
13188
14188
15188
16198
17198
18199
19199
20199
21199
22209
23209
242010
252010
262010
272010
282010
292110
302111

How April really feels in Aso

Once humidity and wind are folded in, April 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

April sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Aso weather by month

How April compares with the rest of the year at a glance. April is the 7th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°698.82.810.11.2
Feb / 929.42.110.81.9
Mar13° / 14012.80.911.73.6
Apr18° / 15811.70.112.85.5
May23° / 13°18112.4013.76.3
Jun25° / 18°41318014.15.2
Jul28° / 21°31918.80144.4
Aug30° / 22°16416.3013.24.4
Sep27° / 18°16512.9012.26.0
Oct22° / 12°1027.7011.27.1
Nov16° / 818.1010.35.3
Dec10° / 698.61.39.92.4

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 12% of April, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24555
34456
44456
54456
64456
74357
84357
94258
104258
114357
124258
134258
144258
154060
164060
174159
184159
194159
204159
214159
224258
234258
244357
254357
264357
274258
284258
294159
304159

Chance of precipitation in April

Any precipitation

Aso gets around 158 mm of rain and snow over 11.7 wet days in April. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 40% and peaks near 41% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%50%151015202530
Rain chance (%)
141
240
340
439
539
638
738
838
938
1038
1139
1239
1340
1440
1540
1641
1741
1841
1941
2041
2141
2241
2341
2441
2541
2641
2741
2840
2940
3040

Humidity in April

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, April lands in the dry band about 86% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
194510
293610
393610
492620
591720
691720
790820
890820
990820
1089920
1189920
1288930
1388930
14871030
15871030
16871030
17871030
18861040
19861040
20861040
21841150
22841150
23831250
24821260
25811360
26791470
27781471
28771571
29761581
30751681

Wind in April

Winds average 8 km/h in April.

Across April, 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
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 18 min at the start of April to 13 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over April. Sunrise moves from 6:11 AM to 5:35 AM, and sunset from 6:29 PM to 6:51 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.36:116:29
212.36:106:30
312.46:086:31
412.46:076:32
512.46:066:32
612.56:046:33
712.56:036:34
812.56:026:35
912.66:006:35
1012.65:596:36
1112.65:586:37
1212.75:576:37
1312.75:556:38
1412.75:546:39
1512.85:536:40
1612.85:516:40
1712.85:506:41
1812.95:496:42
1912.95:486:43
2012.95:476:43
2113.05:456:44
2213.05:446:45
2313.05:436:45
2413.15:426:46
2513.15:416:47
2613.15:406:48
2713.25:396:48
2813.25:376:49
2913.25:366:50
3013.35:356:51

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 4.94 kWh/m².

For context, solar energy here swings from a low near 2.33 kWh/m² to a high of 5.19 kWh/m² in May across the year — April's 4.94 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.7Bright
54.7Bright
64.7Bright
74.7Bright
84.8Bright
94.8Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
144.9Bright
154.9Bright
164.9Bright
174.9Bright
185.0Bright
195.0Bright
205.0Bright
215.0Bright
225.0Bright
235.1Bright
245.1Bright
255.1Bright
265.1Bright
275.1Bright
285.1Bright
295.1Bright
305.2Bright
Planning a trip in April

Hazard calendar for Aso

In seasonPeak

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

Aso sits in the Pacific typhoon belt; the season peaks July–October.

Aso's rainy season runs June–July, when most of the year's rain falls.

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

Is April a good time to visit Aso?

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

5.5
Sightseeing
4th-best month of the year
2.1
Beach & pool
7th-best month of the year

April is a reasonable time to visit Aso for sightseeing.

What to pack for Aso in April

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

In April, Aso sees daytime highs around 18°C and nights near 8°C. Worth packing: rain gear and sun protection. About 12 days see rain.

rain gearsun protection

Sea temperature near Aso in April

The nearest coast averages about 16°C in April — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 43 km away) is warmest in August at about 27°C and coldest in February near 13°C.

It's comfortable for a long swim from May 27 to Nov 13 — about 5.6 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan14Bracing
Feb13Bracing
Mar14Bracing
Apr16Cool
May19Cool
Jun22Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov20Cool
Dec17Cool

UV index in Aso in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April 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 Aso peaks around June 23 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highModerateJun 23UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar7High
Apr8Very high
May9Very high
Jun11Extreme
Jul10Extreme
Aug10Very high
Sep10Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Aso in April

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where April falls, not just the annual average.

Air quality in Aso is worst in March — around 30 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (September, 14 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1829 µg/m³Sep 2214 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb20Moderate
Mar30Moderate
Apr24Moderate
May22Moderate
Jun19Moderate
Jul14Moderate
Aug15Moderate
Sep14Moderate
Oct14Moderate
Nov15Moderate
Dec14Moderate
Location & terrain

Where is Aso?

Aso sits at 32.9°N, 131.1°E, 520 m above sea level, in Japan. The nearest listed city is Ōzu, 20 km away.

Topography around Aso

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

Within 3 km, the terrain around Aso has significant variations in elevation — a maximum elevation change of 428 m around an average of 568 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,443 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,757 m.

The land around Aso is covered by cropland (53%) and trees (29%) within 3 km, trees (65%) and cropland (20%) within 16 km, and trees (71%) within 80 km.

3 km
428 m
16 km
1,443 m
80 km
1,757 m
treesgrasslandcroplandartificial surfaceswater
April weather nearby: Ōzu 20 km · Kikuchi 25 km · Okino 28 km · Kōshi 29 km · Takedamachi 30 km · Shimada 34 km · Mifune 34 km · Kotō 36 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 Aso (32.9373°, 131.0801°, elevation 520 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).