Climate and average weather in Ojiya

In Ojiya, the summers are muggy, hot, wet, and partly cloudy and the winters are cold, snowy, and mostly cloudy.

Best: late April to late June

Over the course of the year, the temperature in Ojiya typically varies from -2°C to 30°C, and is rarely below -6°C or above 35°C. August is the hottest month of the year, while January is the coldest.

Based on the travel score, the best times of year to visit Ojiya for warm-weather activities are from late April to late June and early September to late October.

Hottest
Aug
30°
Coldest
Jan
-2°
Wettest
Jul
243 mm
Driest
Apr
122 mm
Rain / yr
2105 mm
222 wet days
Daylight
9.4–14.6 h
shortest–longest
Elevation
72 m
37.3°N
Clearest
Apr
63% cloud

Ojiya 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 late April to late June.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.7 months, from June 2 to September 23, with daily high temperatures above 24°C. The hottest month of the year in Ojiya is August, with an average high of 30°C and low of 21°C.

The cool season lasts 3.4 months, from December 5 to March 17, with daily high temperatures below 9°C. The coldest month of the year in Ojiya is January, with an average low of -2°C and high of 4°C.

Days typically run about 9°C warmer than nights, with the widest day–night swing (around 11°C) in April.

-10°10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan4-2
Feb5-2
Mar90
Apr165
May2211
Jun2516
Jul2921
Aug3021
Sep2617
Oct2011
Nov135
Dec70

How hot and cold Ojiya 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 hottest afternoons, once humidity is folded in, Ojiya feels like about 34°C (around August 3). About 31 days a year carry some heat stress, peaking in August.

On the coldest nights, wind chill pulls the feels-like down to about -6°C (around January 20), with roughly 123 freezing days a year (feels-like at or below 0°C), worst in January.

-10°10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan44-6-2
Feb55-5-2
Mar99-30
Apr161635
May22221111
Jun25251616
Jul30292121
Aug33302121
Sep26261717
Oct20201111
Nov131335
Dec77-30

Average hourly temperature in Ojiya

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 30°C, and coldest before dawn in January, near -2°C.

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

Ojiya 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 / -2°22725.621.99.70.0
Feb / -2°16821.417.810.60.1
Mar / -0°16220.611.711.71.3
Apr16° / 12215.51.712.94.3
May22° / 11°12713.90146.0
Jun25° / 16°15115.3014.55.7
Jul29° / 21°24319.1014.34.4
Aug30° / 21°17116.7013.44.2
Sep26° / 17°17715.8012.35.5
Oct20° / 11°17415.90115.3
Nov13° / 16618.22.3103.0
Dec / -0°21823.614.29.50.6

Chance of rain

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

Ojiya gets about 2105 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 4.4 months, from around Nov 15 to Mar 29, peaking in January at about 83% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jun 1.

July is the wettest month by volume, with 243 mm over about 19 wet days; April is the driest, with 122 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 23 · 83%Jun 1 · 41%
Rain on a day (%)Rain days
Jan8226
Feb7721
Mar6621
Apr5216
May4514
Jun5215
Jul6119
Aug5417
Sep5416
Oct5116
Nov6118
Dec7624

Monthly rainfall

Over a full year, Ojiya collects about 2105 mm of rain across 222 wet days — roughly 175 mm in an average month.

It doesn’t fall evenly. July is the wettest month with 243 mm, while April is the driest at just 122 mm. The three wettest months alone bring about 33% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200250300JanFebMarAprMayJunJulAugSepOctNovDec227168162122127151243171177174166218
Rainfall (mm)Rain daysSnow days
Jan2272622
Feb1682118
Mar1622112
Apr122162
May127140
Jun151150
Jul243190
Aug171170
Sep177160
Oct174160
Nov166182
Dec2182414

Snow in Ojiya

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.

Ojiya averages about 70 snowy days a year. Snow season runs roughly Nov 1 to Apr 22 — about 5.7 months.

January is snowiest, with roughly 21 days of snow and an estimated 165 cm of snowfall. Over the year that adds up to an estimated 485 cm of snow.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonsnow seasonJan 30
Snow daysSnowfall (cm)
Jan22165
Feb18141
Mar1257
Apr27
May00
Jun00
Jul00
Aug00
Sep00
Oct00
Nov28
Dec14108

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Ojiya, 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 24 and lasts for 2.5 months, ending around June 7. The clearest month is April, when the sky is clear, mostly clear, or partly cloudy 41% of the time on average.

The cloudier part of the year begins around November 21 and lasts for 4.0 months, ending around March 23. The cloudiest month is January, when it is overcast or mostly cloudy 86% 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 17 · 42%Jan 21 · 13%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan1486
Feb2080
Mar2872
Apr4159
May3961
Jun2575
Jul2773
Aug4060
Sep3664
Oct4060
Nov3367
Dec2377

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 16, brings about 14 h 36 min of light; the shortest, around December 16, only 9 h 24 min — a swing of roughly 5 h 12 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan9.77:034:45
Feb10.66:425:17
Mar11.76:035:46
Apr12.95:166:14
May14.04:416:41
Jun14.54:287:02
Jul14.34:407:00
Aug13.45:066:32
Sep12.35:325:46
Oct11.05:595:01
Nov10.06:314:29
Dec9.56:584:24

Sunny days

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

Ojiya averages about 5 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 9 days.

The sunnier stretch runs 2.6 months, from around Mar 25 to Jun 10. The sunniest month is April, with roughly 8 sunny days (gloomy).

The greyest month is January, down near 2 sunny days — about 80% fewer than the April peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedApr 309 daysJan 161 days
Sunny daysSky
Jan2Gloomy
Feb2Gloomy
Mar5Gloomy
Apr8Gloomy
May8Gloomy
Jun4Gloomy
Jul5Gloomy
Aug7Gloomy
Sep5Gloomy
Oct6Gloomy
Nov6Gloomy
Dec3Gloomy

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 Ojiya, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 3.9 months, from around June 6 to October 3. The muggiest month is July, when the air feels humid, muggy or worse about 98% of the time.

The most comfortable stretch runs from around October 4 to June 5, 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 12 · 100%Jul 28 · 0%oppressivehumidcomfortabledrymuggycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb10000000
Mar10000000
Apr9820000
May74215000
Jun1629351830
Jul021343420
Aug01735543
Sep10182732130
Oct682010200
Nov9910000
Dec10000000

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.

Across the year, average wind speed in Ojiya is typically calm, near 7 km/h, and varies little with the seasons.

The windier part of the year lasts 6.4 months, from around Nov 1 to May 15. The windiest month is January, averaging about 8 km/h (calm).

The calmer part of the year runs from around May 16 to Oct 31, with July the calmest month at about 5 km/h.

051015JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezeJan 1 · 8 km/hJul 18 · 5 km/h
Wind speed (km/h)Feels
Jan8calm
Feb8calm
Mar8calm
Apr8calm
May7calm
Jun5calm
Jul5calm
Aug5calm
Sep5calm
Oct6calm
Nov7calm
Dec8calm

Hazard calendar for Ojiya

In seasonPeak

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

Ojiya 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 Ojiya

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around early May, Ojiya 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 times of year to visit Ojiya for general outdoor tourist activities run from late April to late June and again from early September to late October, with a peak score in the first week of June.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationJun 1 · 6.4

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
Feb0.1poor
Mar1.4poor
Apr4.3fair
May6.0good
Jun5.6good
Jul4.4fair
Aug4.3fair
Sep5.5fair
Oct5.3fair
Nov3.0poor
Dec0.6poor

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 Ojiya for hot-weather activities is from late May to late September, with a peak score in the first week of August.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 1 · 5.8

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 Ojiya, 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 30°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 4°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Ojiya sees daytime highs around 30°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 17 days see rain.

Sea temperature near Ojiya

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 18 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 Ojiya 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 Ojiya 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 Ojiya

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
Apr72.5
May84.5
Jun8.55.5
Jul8.55.5
Aug85.5
Sep74
Oct50
Nov1.50
Dec00

Air quality in Ojiya 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 Ojiya is worst in April — around 23 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1723 µg/m³Dec 1610 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb15Moderate
Mar22Moderate
Apr23Moderate
May22Moderate
Jun19Moderate
Jul17Moderate
Aug14Moderate
Sep12Moderate
Oct12Good
Nov11Good
Dec10Good
Almanac & agriculture

Growing season

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

The growing season in Ojiya typically lasts about 268 days, from around March 19 to December 11 — the span where a frost-free day is more likely than not. It is reliably frost-free from April 11 to November 17.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecgrowing seasonMar 1950%Apr 1190%Nov 1790%Dec 1150%
Frost-free chance (%)Frost nights
Jan1731
Feb1828
Mar4831
Apr9210
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov9013
Dec4431

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. Ojiya banks about 2,013 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

05001,0001,5002,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr36
May202
Jun323
Jul450
Aug486
Sep344
Oct163
Nov10
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.

Ojiya receives about 3.9 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 1.9 and 5.8 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 8 to Sep 15. The brightest month is May, averaging about 5.7 kWh/m² (bright).

The dimmest month is December, down near 1.9 kWh/m² — roughly 67% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 285.8 kWhDec 131.9 kWh
Solar energy (kWh/m²)Level
Jan2.2Moderate
Feb3.1Moderate
Mar4.2Bright
Apr5.2Bright
May5.7Bright
Jun5.4Bright
Jul5.0Bright
Aug5.1Bright
Sep4.0Moderate
Oct3.1Moderate
Nov2.3Moderate
Dec1.9Dim

Where is Ojiya?

Ojiya sits at 37.3°N, 138.8°E, 72 m above sea level, in Japan. The nearest listed city is Uonuma, 16 km away.

Topography around Ojiya

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

Within 3 km, the terrain around Ojiya has significant variations in elevation — a maximum elevation change of 296 m around an average of 107 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 711 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,554 m.

The land around Ojiya is covered by trees (42%), cropland (22%) and artificial surfaces (22%) within 3 km, trees (74%) within 16 km, and trees (62%) and water (26%) within 80 km.

3 km
296 m
16 km
711 m
80 km
2,554 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Uonuma 16 km · Nagaoka 17 km · Tōkamachi 19 km · Kashiwazaki 23 km · Minamiuonuma 25 km · Tochio-honchō 26 km · Muikamachi 27 km · Mitsuke 28 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 Ojiya (37.3°, 138.8°, elevation 72 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).