Rumoi weather in April

In April, Rumoi sees average daytime highs of 8°C and overnight lows near 1°C, with 66 mm of precipitation across 11.9 wet days and about 13.2 hours of daylight. It is the 7th-warmest and 10th-wettest month of the year here.

Highs climb over the month, from about 6°C in the first days to 11°C by the end. The sky is clear or mostly clear about 31% of the time in April, and the air most often feels dry.

Daylight stretches from about 12 h 30 min at the start of April to 13 h 54 min by month's end. Set against the rest of the year, April is Rumoi's 1st-clearest and 6th-windiest month. For the whole year in context, see Rumoi's year-round climate.

Daytime high
7th warmest
Overnight low
6th coldest
Precipitation
66 mm
11.9 wet days
Daylight
13 h 12 min
4:57 AM – 6:10 PM
Cloud cover
59%
1st clearest
Wind
12 km/h
6th windiest
Solar energy
5.14 kWh/m²
Travel score
1.5
out of 10

Rumoi is city in Hokkaido, Japan.

Density
89/km²
people per km²
Founded
1947

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 6°C in the first days to 11°C by the end.

A typical April day in Rumoi reaches about 8°C in the afternoon and slips back to 1°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 4°C and 13°C. Set against its neighbours, April runs about 6°C warmer than March and about 5°C cooler than May.

-10°10°20°151015202530
Avg high (°C)Avg low (°C)
15-2
26-1
36-1
46-1
56-1
67-1
770
870
970
1070
1180
1281
1381
1481
1581
1692
1792
1892
1992
2092
21103
22103
23103
24103
25103
26114
27114
28114
29114
30115

How April really feels in Rumoi

Once humidity and wind are folded in, April averages 0 days that feel above 32°C and 23 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
23
wind chill below the day's low

The story in April is cold — wind chill drags the overnight "feels like" below the raw low.

Rumoi weather by month

How April compares with the rest of the year at a glance. April is the 7th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-3° / -9°6717.3219.10.0
Feb-2° / -8°5514.217.110.20.0
Mar / -5°6613.614.111.60.0
Apr / 6611.94.613.21.5
May14° / 7811.70.314.53.8
Jun18° / 12°7010.4015.25.6
Jul22° / 17°12112.4014.96.2
Aug24° / 18°14313.7013.86.2
Sep20° / 14°13713.9012.35.7
Oct14° / 11515.90.310.83.6
Nov / 12419.411.49.40.7
Dec-0° / -5°10221.622.68.80.0

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time in April, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 15% of April, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14753
24852
34753
44852
54852
64753
74852
84852
94852
104753
114753
124753
134753
144753
154753
164654
174654
184654
194654
204654
214555
224555
234555
244555
254456
264555
274555
284456
294456
304456

Chance of precipitation in April

Any precipitationSnow

Rumoi gets around 66 mm of rain and snow over 11.9 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 42% on the wettest days, and about 5 days bring snow.

0%10%20%30%40%50%151015202530
Rain chance (%)Snow chance (%)
13828
23826
33825
43824
53823
63822
73821
83920
93919
103919
113918
123917
133917
143916
154016
164015
174014
184014
194013
204012
214012
224111
234111
244110
25419
26418
27428
28427
29426
30426

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 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100

Wind in April

Winds average 12 km/h in April.

Across April, daily wind ranges from about 12 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 30 min at the start of April to 13 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 84 minutes over April. Sunrise moves from 5:25 AM to 4:34 AM, and sunset from 5:52 PM to 6:27 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.55:255:52
212.55:235:53
312.65:215:54
412.65:195:55
512.75:175:57
612.75:155:58
712.85:135:59
812.85:126:00
912.95:106:01
1012.95:086:03
1113.05:066:04
1213.05:046:05
1313.15:036:06
1413.15:016:08
1513.24:596:09
1613.24:576:10
1713.34:566:11
1813.34:546:12
1913.44:526:14
2013.44:506:15
2113.54:496:16
2213.54:476:17
2313.64:456:19
2413.64:446:20
2513.64:426:21
2613.74:416:22
2713.74:396:23
2813.84:376:25
2913.84:366:26
3013.94:346:27

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 5.14 kWh/m².

For context, solar energy here swings from a low near 1.43 kWh/m² to a high of 5.5 kWh/m² in May across the year — April's 5.14 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
105.0Bright
115.1Bright
125.1Bright
135.1Bright
145.1Bright
155.1Bright
165.1Bright
175.1Bright
185.1Bright
195.2Bright
205.2Bright
215.2Bright
225.2Bright
235.2Bright
245.2Bright
255.3Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
Planning a trip in April

Hazard calendar for Rumoi

In seasonPeak

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

Rumoi 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 April a good time to visit Rumoi?

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

1.5
Sightseeing
7th-best month of the year
0.0
Beach & pool
7th-best month of the year

April is a weaker month for outdoor sightseeing in Rumoi.

What to pack for Rumoi in April

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

In April, Rumoi sees daytime highs around 8°C and nights near 1°C. Pack a warm layer. Worth having: rain gear and sun protection. About 12 days see rain.

a warm layerrain gearsun protection

Sea temperature near Rumoi in April

The nearest coast averages about 7°C in April — 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 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 Rumoi in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Rumoi peaks around August 15 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 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighHighVery highHighModerateLowAug 15UV 8Dec 20UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr5High
May7Very high
Jun7High
Jul7High
Aug8Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Rumoi 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 Rumoi is worst in April — around 17 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (December, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1317 µg/m³Dec 217 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb10Good
Mar16Moderate
Apr17Moderate
May15Moderate
Jun10Good
Jul10Good
Aug8Good
Sep7Good
Oct9Good
Nov9Good
Dec7Good
Location & terrain

Where is Rumoi?

Rumoi sits at 43.9°N, 141.6°E, 35 m above sea level, in Japan. The nearest listed city is Fukagawa, 41 km away.

Topography around Rumoi

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

Within 3 km, the terrain around Rumoi has only modest variations in elevation — a maximum elevation change of 248 m around an average of 40 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 731 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,471 m.

The land around Rumoi is covered by trees (41%) and water (34%) within 3 km, trees (53%) and water (40%) within 16 km, and trees (51%) and water (35%) within 80 km.

3 km
248 m
16 km
731 m
80 km
1,471 m
treesgrasslandcroplandartificial surfaceswater
April weather nearby: Fukagawa 41 km · Takikawa 47 km · Sunagawa 54 km · Asahikawa 61 km · Minamishibetsuchō 63 km · Ashibetsu 64 km · Bibai 70 km · Nayoro 80 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 Rumoi (43.9344°, 141.6428°, elevation 35 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).