Climate and average weather in Muikamachi

In Muikamachi, the summers are humid, warm, wet, and partly cloudy and the winters are very cold, snowy, and mostly cloudy.

Best: mid May to mid October

Over the course of the year, the temperature in Muikamachi typically varies from -7°C to 26°C, and is rarely below -10°C or above 29°C. August is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Muikamachi for warm-weather activities is from mid May to mid October.

Hottest
Aug
26°
Coldest
Jan
-7°
Wettest
Jul
249 mm
Driest
Apr
134 mm
Rain / yr
2131 mm
229 wet days
Daylight
9.5–14.5 h
shortest–longest
Elevation
162 m
37.1°N
Clearest
Apr
65% cloud

Muikamachi is dissolved municipality in Minamiuonuma district, Niigata prefecture, Japan.

Founded
1900

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

Muikamachi weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around mid May to mid October.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Muikamachi, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 3.8 months, from June 3 to September 25, with daily high temperatures above 20°C. The hottest month of the year in Muikamachi is August, with an average high of 26°C and low of 18°C.

The cool season lasts 3.5 months, from December 4 to March 20, with daily high temperatures below 5°C. The coldest month of the year in Muikamachi is January, with an average low of -7°C and high of -1°C.

Days typically run about 8°C warmer than nights, with the widest day–night swing (around 9°C) in May.

-10°10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan0-7
Feb1-6
Mar4-3
Apr111
May178
Jun2113
Jul2417
Aug2618
Sep2214
Oct168
Nov91
Dec3-5

How hot and cold Muikamachi really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the coldest nights, wind chill pulls the feels-like down to about -10°C (around January 19), with roughly 157 freezing days a year (feels-like at or below 0°C) 28 of them bitterly cold — worst in January.

-10°10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan00-10-7
Feb01-9-6
Mar44-7-3
Apr1011-11
May171778
Jun21211313
Jul24241717
Aug26261818
Sep22221414
Oct161678
Nov99-11
Dec33-8-5

Average hourly temperature in Muikamachi

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on August afternoons, near 26°C, and coldest before dawn in January, near -7°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Muikamachi weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-1° / -7°21325.225.49.70.0
Feb / -6°16720.820.610.60.0
Mar / -4°16821.118.311.70.1
Apr11° / 13416.76.212.92.1
May17° / 14515.20.6144.8
Jun21° / 13°17917.3014.55.0
Jul24° / 17°24921.1014.35.0
Aug26° / 18°17718013.45.5
Sep22° / 14°18816.3012.35.3
Oct16° / 17716.30.5114.1
Nov / 14418.27.4101.5
Dec / -5°19022.920.19.50.0

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Muikamachi gets about 2131 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 4.3 months, from around Nov 19 to Mar 30, peaking in January at about 82% chance on a given day. The drier stretch runs the rest of the year, bottoming out around May 29.

July is the wettest month by volume, with 249 mm over about 21 wet days; April is the driest, with 134 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%70%80%90%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetJan 28 · 82%May 29 · 46%
Rain on a day (%)Rain days
Jan8125
Feb7621
Mar6721
Apr5517
May4915
Jun5917
Jul6721
Aug5818
Sep5616
Oct5216
Nov6118
Dec7423

Monthly rainfall

Over a full year, Muikamachi collects about 2131 mm of rain across 229 wet days — roughly 178 mm in an average month.

It doesn’t fall evenly. July is the wettest month with 249 mm, while April is the driest at just 134 mm. The three wettest months alone bring about 31% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200250300JanFebMarAprMayJunJulAugSepOctNovDec213167168134145179249177188177144190
Rainfall (mm)Rain daysSnow days
Jan2132525
Feb1672121
Mar1682118
Apr134176
May145151
Jun179170
Jul249210
Aug177180
Sep188160
Oct177161
Nov144187
Dec1902320

Snow in Muikamachi

Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.

Muikamachi averages about 99 snowy days a year. Snow season runs roughly Oct 19 to May 15 — about 6.9 months.

January is snowiest, with roughly 25 days of snow and an estimated 194 cm of snowfall. Over the year that adds up to an estimated 713 cm of snow.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonsnow seasonJan 24
Snow daysSnowfall (cm)
Jan25194
Feb21180
Mar18116
Apr630
May12
Jun00
Jul00
Aug00
Sep00
Oct11
Nov742
Dec20150

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Muikamachi, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around March 15 and lasts for 2.7 months, ending around June 3. The clearest month is April, when the sky is clear, mostly clear, or partly cloudy 38% of the time on average.

The cloudier part of the year begins around June 4 and lasts for 1.6 months, ending around July 22. The cloudiest month is January, when it is overcast or mostly cloudy 82% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecApr 15 · 39%Jun 29 · 16%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan1882
Feb2179
Mar2971
Apr3862
May3565
Jun2179
Jul2476
Aug3664
Sep3070
Oct3466
Nov3466
Dec2773

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 8, brings about 14 h 30 min of light; the shortest, around January 1, only 9 h 30 min — a swing of roughly 5 hours.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan9.77:024:45
Feb10.66:415:17
Mar11.76:035:45
Apr12.95:166:13
May14.04:416:40
Jun14.54:297:01
Jul14.34:417:00
Aug13.45:066:32
Sep12.35:325:46
Oct11.05:595:00
Nov10.06:304:29
Dec9.56:574:25

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Muikamachi averages about 5 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 8 days.

The sunnier stretch runs 2.9 months, from around Mar 11 to Jun 7. The sunniest month is April, with roughly 7 sunny days (gloomy).

The greyest month is June, down near 3 sunny days — about 55% fewer than the April peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedApr 278 daysJun 272 days
Sunny daysSky
Jan2Gloomy
Feb3Gloomy
Mar5Gloomy
Apr7Gloomy
May7Gloomy
Jun3Gloomy
Jul3Gloomy
Aug6Gloomy
Sep4Gloomy
Oct6Gloomy
Nov6Gloomy
Dec4Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Muikamachi, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 3.3 months, from around June 18 to September 24. The muggiest month is August, when the air feels humid, muggy or worse about 90% of the time.

The most comfortable stretch runs from around September 25 to June 17, and April is the most comfortable month — the air is dry or comfortable 100% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecApr 21 · 100%Aug 4 · 5%muggycomfortabledryhumidcomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
Jan1000000
Feb1000000
Mar1000000
Apr1000000
May955100
Jun45341830
Jul21641401
Aug1933552
Sep302730130
Oct8810200
Nov1000000
Dec1000000

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in Muikamachi is steady company: average speeds sit near 6 km/hcalm — in every month of the year, with no meaningful windy or calm season.

051015JanFebMarAprMayJunJulAugSepOctNovDeccalmlight breezeFeb 22 · 7 km/hJul 19 · 5 km/h
Wind speed (km/h)Feels
Jan7calm
Feb7calm
Mar7calm
Apr7calm
May6calm
Jun5calm
Jul5calm
Aug5calm
Sep5calm
Oct6calm
Nov6calm
Dec7calm

Hazard calendar for Muikamachi

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Muikamachi 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

Best time to visit Muikamachi

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Muikamachi throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late May, Muikamachi is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Muikamachi for general outdoor tourist activities is from mid May to mid October, with a peak score in the first week of September.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationSep 4 · 5.5

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan0.0poor
Feb0.0poor
Mar0.1poor
Apr2.1poor
May4.8fair
Jun5.0fair
Jul5.0fair
Aug5.5fair
Sep5.3fair
Oct4.1fair
Nov1.5poor
Dec0.0poor

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Muikamachi for hot-weather activities is from mid July to early September, with a peak score in the first week of August.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 5 · 5.3

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Muikamachi, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around August (highs near 26°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near -1°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Muikamachi sees daytime highs around 26°C and nights near 18°C. Pack rain gear. Worth having: light clothes and sun protection. About 18 days see rain.

Sea temperature near Muikamachi

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea at the nearest coast (about 41 km away) is warmest in August at about 27°C and coldest in March near 10°C.

It's comfortable for a long swim from Jun 21 to Oct 31 — about 4.4 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan12Bracing
Feb11Bracing
Mar10Bracing
Apr11Bracing
May15Bracing
Jun20Cool
Jul23Refreshing
Aug27Warm
Sep25Warm
Oct22Refreshing
Nov18Cool
Dec15Cool

UV index (midday) in Muikamachi by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Muikamachi peaks around August 12 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 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 highModerateAug 12UV 10Dec 21UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun9Very high
Jul10Very high
Aug10Very high
Sep8Very high
Oct5High
Nov3Moderate
Dec2Moderate

Average hourly UV index in Muikamachi

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in August the burn window is concentrated in the middle of the day: about 8 hours a day reach index 3 (protection recommended), and 5.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan00
Feb30
Mar4.50
Apr6.52.5
May84.5
Jun8.55.5
Jul8.55.5
Aug85.5
Sep74
Oct50
Nov1.50
Dec00

Air quality in Muikamachi by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Muikamachi is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1821 µg/m³Dec 1610 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun18Moderate
Jul15Moderate
Aug13Moderate
Sep12Good
Oct12Good
Nov11Good
Dec10Good
Almanac & agriculture

Growing season

Chance of a frost-free dayTypical season (≥50%)

The growing season in Muikamachi typically lasts about 226 days, from around April 9 to November 20 — the span where a frost-free day is more likely than not. It is reliably frost-free from April 30 to November 1.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecgrowing seasonMar 910%Apr 950%Apr 3090%Nov 190%Nov 2050%Dec 1510%
Frost-free chance (%)Frost nights
Jan131
Feb328
Mar1631
Apr6428
May980
Jun1000
Jul1000
Aug1000
Sep1000
Oct980
Nov6129
Dec1231

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Muikamachi banks about 1,298 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

05001,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr0
May81
Jun209
Jul338
Aug368
Sep240
Oct61
Nov0
Dec0

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Muikamachi receives about 3.9 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 2.1 and 5.6 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 4 to Sep 11. The brightest month is May, averaging about 5.6 kWh/m² (bright).

The dimmest month is December, down near 2.1 kWh/m² — roughly 62% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 255.6 kWhDec 142.1 kWh
Solar energy (kWh/m²)Level
Jan2.4Moderate
Feb3.3Moderate
Mar4.4Bright
Apr5.3Bright
May5.6Bright
Jun5.1Bright
Jul4.8Bright
Aug4.9Bright
Sep3.8Moderate
Oct3.1Moderate
Nov2.4Moderate
Dec2.1Moderate

Where is Muikamachi?

Muikamachi sits at 37.1°N, 138.9°E, 162 m above sea level, in Japan. The nearest listed city is Minamiuonuma, 2.0 km away.

Topography around Muikamachi

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

Within 3 km, the terrain around Muikamachi has significant variations in elevation — a maximum elevation change of 461 m around an average of 231 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,862 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,551 m.

The land around Muikamachi is covered by trees (43%) and cropland (33%) within 3 km, trees (77%) within 16 km, and trees (75%) within 80 km.

3 km
461 m
16 km
1,862 m
80 km
2,551 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Minamiuonuma 2.0 km · Shiozawa 4.0 km · Tōkamachi 13 km · Uonuma 21 km · Ojiya 27 km · Nagaoka 43 km · Minakami 43 km · Kashiwazaki 45 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 Muikamachi (37.0667°, 138.8833°, elevation 162 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).