Climate and average weather in Tonami

In Tonami, the summers are humid, 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 Tonami typically varies from -4°C to 29°C, and is rarely below -8°C or above 33°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 Tonami for warm-weather activities are from late April to late June and late August to late October.

Hottest
Aug
29°
Coldest
Jan
-4°
Wettest
Jul
332 mm
Driest
Apr
175 mm
Rain / yr
2752 mm
233 wet days
Daylight
9.5–14.5 h
shortest–longest
Elevation
61 m
36.6°N
Clearest
Apr
63% cloud

Tonami is city in Toyama Prefecture, Japan.

Density
383/km²
people per km²
Founded
2004

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

Tonami 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 Tonami, 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 3 to September 24, with daily high temperatures above 23°C. The hottest month of the year in Tonami is August, with an average high of 29°C and low of 21°C.

The cool season lasts 3.3 months, from December 6 to March 14, with daily high temperatures below 8°C. The coldest month of the year in Tonami is January, with an average low of -4°C and high of 3°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)
Jan3-4
Feb4-4
Mar8-1
Apr154
May2110
Jun2416
Jul2820
Aug2921
Sep2416
Oct1910
Nov134
Dec6-2

How hot and cold Tonami 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 -8°C (around January 30), with roughly 133 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)
Jan33-7-4
Feb44-7-4
Mar88-4-1
Apr151524
May21211010
Jun24241516
Jul29282020
Aug31292121
Sep24241616
Oct1919910
Nov131324
Dec66-4-2

Average hourly temperature in Tonami

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 29°C, and coldest before dawn in January, near -4°C.

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

Tonami 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 / -4°23024.222.19.80.0
Feb / -4°17920.217.610.60.0
Mar / -1°20720.212.911.71.2
Apr15° / 17515.83.212.93.9
May21° / 10°18615.40.113.95.6
Jun24° / 16°24718.1014.55.3
Jul28° / 20°33221.7014.24.4
Aug29° / 21°24920.4013.44.3
Sep24° / 16°28918.5012.25.2
Oct19° / 10°223170.211.15.0
Nov13° / 19918.44.3102.7
Dec / -2°23722.816.39.50.4

Chance of rain

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

Tonami gets about 2752 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 3.9 months, from around Nov 20 to Mar 18, peaking in January at about 80% chance on a given day. The drier stretch runs the rest of the year, bottoming out around May 1.

July is the wettest month by volume, with 332 mm over about 22 wet days; April is the driest, with 175 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 29 · 80%May 1 · 48%
Rain on a day (%)Rain days
Jan7824
Feb7320
Mar6420
Apr5316
May4915
Jun6118
Jul7022
Aug6520
Sep6219
Oct5417
Nov6218
Dec7423

Monthly rainfall

Over a full year, Tonami collects about 2752 mm of rain across 233 wet days — roughly 229 mm in an average month.

It doesn’t fall evenly. July is the wettest month with 332 mm, while April is the driest at just 175 mm. The three wettest months alone bring about 32% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200250300350400JanFebMarAprMayJunJulAugSepOctNovDec230179207175186247332249289223199237
Rainfall (mm)Rain daysSnow days
Jan2302422
Feb1792018
Mar2072013
Apr175163
May186150
Jun247180
Jul332220
Aug249200
Sep289190
Oct223170
Nov199184
Dec2372316

Snow in Tonami

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.

Tonami averages about 77 snowy days a year. Snow season runs roughly Oct 25 to May 1 — about 6.2 months.

January is snowiest, with roughly 21 days of snow and an estimated 154 cm of snowfall. Over the year that adds up to an estimated 517 cm of snow.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonsnow seasonJan 28
Snow daysSnowfall (cm)
Jan22154
Feb18140
Mar1375
Apr311
May00
Jun00
Jul00
Aug00
Sep00
Oct00
Nov422
Dec16115

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Tonami, 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 September 27 and lasts for 1.9 months, ending around November 24. 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 June 1 and lasts for 1.7 months, ending around July 23. The cloudiest month is January, when it is overcast or mostly cloudy 80% 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%JanFebMarAprMayJunJulAugSepOctNovDecOct 28 · 43%Jun 29 · 16%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2080
Feb2377
Mar3466
Apr4159
May3862
Jun2179
Jul2575
Aug3862
Sep3268
Oct3961
Nov3664
Dec2575

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 12, 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)
Jan9.87:094:54
Feb10.66:495:25
Mar11.76:115:53
Apr12.95:246:20
May13.94:506:47
Jun14.54:387:07
Jul14.24:507:06
Aug13.45:146:39
Sep12.25:405:53
Oct11.16:065:09
Nov10.06:374:38
Dec9.57:034:34

Sunny days

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

Tonami 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 9 days.

The sunnier stretch runs 2.9 months, from around Mar 11 to Jun 5. The sunniest month is April, with roughly 8 sunny days (gloomy).

The greyest month is June, down near 3 sunny days — about 57% fewer than the April peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedApr 309 daysJun 272 days
Sunny daysSky
Jan2Gloomy
Feb3Gloomy
Mar5Gloomy
Apr8Gloomy
May8Gloomy
Jun3Gloomy
Jul4Gloomy
Aug6Gloomy
Sep4Gloomy
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 Tonami, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 3.8 months, from around June 8 to September 30. The muggiest month is August, when the air feels humid, muggy or worse about 98% of the time.

The most comfortable stretch runs from around October 1 to June 7, 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 9 · 100%Aug 2 · 0%oppressivemuggycomfortabledryhumidcomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
Jan1000000
Feb1000000
Mar1000000
Apr982000
May7818400
Jun173234161
Jul02185525
Aug02104841
Sep122230325
Oct7020810
Nov991000
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 Tonami is steady company: average speeds sit near 6 km/hcalm — in every month of the year, with no meaningful windy or calm season.

051015JanFebMarAprMayJunJulAugSepOctNovDeccalmlight breezeApr 15 · 8 km/hAug 19 · 5 km/h
Wind speed (km/h)Feels
Jan7calm
Feb7calm
Mar8calm
Apr8calm
May7calm
Jun6calm
Jul6calm
Aug5calm
Sep5calm
Oct6calm
Nov7calm
Dec7calm

Hazard calendar for Tonami

In seasonPeak

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

Tonami 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 Tonami

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around early May, Tonami 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 Tonami for general outdoor tourist activities run from late April to late June and again from late August to late October, with a peak score in the last week of May.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMay 30 · 5.8

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
Mar1.2poor
Apr3.9fair
May5.6good
Jun5.2fair
Jul4.4fair
Aug4.3fair
Sep5.2fair
Oct5.0fair
Nov2.7poor
Dec0.5poor

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

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 1 · 5.4

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 Tonami, 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 29°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 3°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Tonami sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 20 days see rain.

Sea temperature near Tonami

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 28 km away) is warmest in August at about 27°C and coldest in March near 11°C.

It's comfortable for a long swim from Jun 17 to Nov 3 — about 4.6 months when the water holds above 20°C.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan13Bracing
Feb11Bracing
Mar11Bracing
Apr12Bracing
May16Cool
Jun20Cool
Jul24Refreshing
Aug27Warm
Sep25Warm
Oct22Refreshing
Nov19Cool
Dec16Cool

UV index (midday) in Tonami 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 Tonami peaks around August 14 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateAug 14UV 10Dec 23UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug10Very high
Sep9Very high
Oct5High
Nov3Moderate
Dec2Low

Average hourly UV index in Tonami

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
Feb1.50
Mar40
Apr60
May7.54.5
Jun85
Jul8.55.5
Aug85.5
Sep74.5
Oct50
Nov00
Dec00

Air quality in Tonami 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 Tonami is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1621 µg/m³Dec 139 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar20Moderate
Apr21Moderate
May20Moderate
Jun18Moderate
Jul14Moderate
Aug12Good
Sep10Good
Oct10Good
Nov10Good
Dec9Good
Almanac & agriculture

Growing season

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

The growing season in Tonami typically lasts about 256 days, from around March 25 to December 5 — the span where a frost-free day is more likely than not. It is reliably frost-free from April 17 to November 10.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecgrowing seasonFeb 1610%Mar 2550%Apr 1790%Nov 1090%Dec 550%Jan 1110%
Frost-free chance (%)Frost nights
Jan931
Feb1128
Mar3931
Apr8616
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct990
Nov8319
Dec3131

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. Tonami banks about 1,802 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
Apr22
May172
Jun289
Jul425
Aug454
Sep309
Oct129
Nov3
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.

Tonami receives about 4.0 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.0 and 5.8 kWh/m².

The brighter stretch of the year lasts 6.4 months, from around Mar 7 to Sep 16. The brightest month is May, averaging about 5.7 kWh/m² (bright).

The dimmest month is December, down near 2.1 kWh/m² — roughly 64% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 275.8 kWhDec 132.0 kWh
Solar energy (kWh/m²)Level
Jan2.4Moderate
Feb3.3Moderate
Mar4.3Bright
Apr5.3Bright
May5.7Bright
Jun5.3Bright
Jul4.9Bright
Aug5.1Bright
Sep4.0Bright
Oct3.3Moderate
Nov2.4Moderate
Dec2.0Moderate

Where is Tonami?

Tonami sits at 36.6°N, 136.9°E, 61 m above sea level, in Japan. The nearest listed city is Nanto-shi, 6.0 km away.

Topography around Tonami

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

Within 3 km, the terrain around Tonami has only modest variations in elevation — a maximum elevation change of 40 m around an average of 58 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,140 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,132 m.

The land around Tonami is covered by cropland (62%) and artificial surfaces (32%) within 3 km, trees (52%) and cropland (31%) within 16 km, and trees (57%) and water (32%) within 80 km.

3 km
40 m
16 km
1,140 m
80 km
3,132 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Nanto-shi 6.0 km · Fukumitsu 10 km · Oyabe 10 km · Nanto 13 km · Takaoka 16 km · Yatsuomachi-higashikumisaka 18 km · Tsubata 19 km · Nishishinminato 21 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 Tonami (36.6205°, 136.9432°, elevation 61 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).