Climate and average weather in Numazu

In Numazu, the summers are muggy, warm, showery, and partly cloudy and the winters are cool and mostly clear.

Best: late April to mid November

Over the course of the year, the temperature in Numazu typically varies from 5°C to 27°C, and is rarely below 2°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 Numazu for warm-weather activities is from late April to mid November.

Hottest
Aug
27°
Coldest
Jan
Wettest
Jul
294 mm
Driest
Dec
89 mm
Rain / yr
2330 mm
151 wet days
Daylight
9.6–14.4 h
shortest–longest
Elevation
8 m
35.1°N
Clearest
Dec
39% cloud

Numazu is city in Shizuoka Prefecture, Japan.

Founded
1923

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

Numazu 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 mid November.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.4 months, from June 20 to October 1, with daily high temperatures above 23°C. The hottest month of the year in Numazu is August, with an average high of 27°C and low of 24°C.

The cool season lasts 3.4 months, from December 9 to March 21, with daily high temperatures below 12°C. The coldest month of the year in Numazu is January, with an average low of 5°C and high of 9°C.

Days typically run about 4°C warmer than nights year-round.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan95
Feb95
Mar127
Apr1611
May1915
Jun2219
Jul2623
Aug2724
Sep2522
Oct2017
Nov1612
Dec128

Average hourly temperature in Numazu

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 27°C, and coldest before dawn in January, near C.

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

Numazu 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 / 968.50.79.92.0
Feb / 1179.10.910.72.1
Mar12° / 204140.511.72.9
Apr16° / 11°21513.1012.94.5
May19° / 15°23212.8013.85.7
Jun22° / 19°28615.8014.35.4
Jul26° / 23°29416.5014.15.6
Aug27° / 24°16514.2013.35.9
Sep25° / 22°24314.5012.26.0
Oct20° / 17°24513.1011.16.0
Nov16° / 12°14410.8010.25.0
Dec12° / 898.40.19.73.3

Chance of rain

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

Numazu gets about 2330 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 4.5 months, from around Jun 2 to Oct 16, peaking in June at about 60% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Dec 29.

July is the wettest month by volume, with 294 mm over about 17 wet days; December is the driest, with 89 mm.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJun 28 · 60%Dec 29 · 23%
Rain on a day (%)Rain days
Jan289
Feb339
Mar4414
Apr4413
May4113
Jun5316
Jul5317
Aug4614
Sep4815
Oct4213
Nov3611
Dec278

Monthly rainfall

Over a full year, Numazu collects about 2330 mm of rain across 151 wet days — roughly 194 mm in an average month.

It doesn’t fall evenly. July is the wettest month with 294 mm, while December is the driest at just 89 mm. The three wettest months alone bring about 35% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200250300350JanFebMarAprMayJunJulAugSepOctNovDec9611720421523228629416524324514489
Rainfall (mm)Rain daysSnow days
Jan9691
Feb11791
Mar204141
Apr215130
May232130
Jun286160
Jul294170
Aug165140
Sep243150
Oct245130
Nov144110
Dec8980

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

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

The clearer part of the year begins around October 13 and lasts for 5.3 months, ending around March 21. The clearest month is December, when the sky is clear, mostly clear, or partly cloudy 69% of the time on average.

The cloudier part of the year begins around March 22 and lasts for 4.9 months, ending around August 17. The cloudiest month is June, when it is overcast or mostly cloudy 78% 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%JanFebMarAprMayJunJulAugSepOctNovDecDec 30 · 73%Jun 20 · 19%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan6733
Feb6040
Mar5050
Apr4654
May3763
Jun2278
Jul3169
Aug4852
Sep4456
Oct5149
Nov6040
Dec6931

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 17, brings about 14 h 24 min of light; the shortest, around December 16, only 9 h 36 min — a swing of roughly 4 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan9.96:574:50
Feb10.76:395:20
Mar11.76:025:46
Apr12.95:186:11
May13.84:466:36
Jun14.34:346:55
Jul14.14:466:55
Aug13.35:096:29
Sep12.25:325:45
Oct11.15:575:03
Nov10.26:264:34
Dec9.76:514:30

Sunny days

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

Numazu averages about 11 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 3 and 19 days.

The sunnier stretch runs 5.0 months, from around Oct 12 to Mar 12. The sunniest month is December, with roughly 17 sunny days (bright).

The greyest month is June, down near 4 sunny days — about 78% fewer than the December peak.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantDec 3019 daysJun 213 days
Sunny daysSky
Jan17Bright
Feb13Mixed
Mar11Mixed
Apr10Mixed
May8Gloomy
Jun4Gloomy
Jul6Gloomy
Aug10Mixed
Sep9Mixed
Oct12Mixed
Nov14Mixed
Dec18Bright

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

The more humid part of the year lasts 4.7 months, from around May 23 to October 12. The muggiest month is July, when the air feels humid, muggy or worse about 99% of the time.

The most comfortable stretch runs from around October 13 to May 22, and March 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%JanFebMarAprMayJunJulAugSepOctNovDecMar 6 · 100%Jul 18 · 0%miserableoppressivehumidmuggycomfortabledrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb10000000
Mar9910000
Apr83152000
May314324300
Jun2153835100
Jul01627589
Aug004155823
Sep3102129333
Oct3632211010
Nov83133000
Dec9910000

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 Numazu is typically calm, near 11 km/h, and varies little with the seasons.

The windier part of the year lasts 5.5 months, from around Nov 12 to Apr 27. The windiest month is January, averaging about 13 km/h (light breeze).

The calmer part of the year runs from around Apr 28 to Oct 2, with July the calmest month at about 9 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezeJan 1 · 13 km/hJul 30 · 9 km/h
Wind speed (km/h)Feels
Jan13light breeze
Feb12light breeze
Mar12light breeze
Apr11calm
May10calm
Jun9calm
Jul9calm
Aug9calm
Sep10calm
Oct11calm
Nov11calm
Dec12light breeze

Hazard calendar for Numazu

In seasonPeak

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

Numazu 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 Numazu

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around early May, Numazu 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 Numazu for general outdoor tourist activities is from late April to mid November, with a peak score in the third week of September.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationSep 20 · 6.1

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
Jan2.0poor
Feb2.1poor
Mar2.9poor
Apr4.5fair
May5.6good
Jun5.4fair
Jul5.6good
Aug5.9good
Sep6.0good
Oct6.0good
Nov5.0fair
Dec3.3poor

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 Numazu for hot-weather activities is from early July to late September, with a peak score in the third week of August.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 21 · 6.0

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 Numazu, 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 27°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 9°C), pack a warm layer and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Numazu sees daytime highs around 27°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 14 days see rain.

Sea temperature near Numazu

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 22 km away) is warmest in August at about 27°C and coldest in February near 15°C.

It's comfortable for a long swim from May 30 to Nov 23 — about 5.9 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Cool
Mar15Cool
Apr17Cool
May19Cool
Jun22Refreshing
Jul24Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov21Refreshing
Dec18Cool

UV index (midday) in Numazu 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 Numazu peaks around July 19 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 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 highExtremeVery highModerateJul 19UV 10Dec 23UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May9Very high
Jun10Very high
Jul10Extreme
Aug10Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Average hourly UV index in Numazu

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 July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6 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
Feb40
Mar50
Apr73
May85
Jun8.56
Jul8.56
Aug85.5
Sep74.5
Oct5.50
Nov30
Dec00

Air quality in Numazu 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 Numazu is worst in April — around 23 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (December, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1623 µg/m³Dec 1610 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb20Moderate
Mar20Moderate
Apr23Moderate
May20Moderate
Jun17Moderate
Jul13Moderate
Aug12Good
Sep12Good
Oct12Good
Nov11Good
Dec10Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Numazu is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb990
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

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. Numazu banks about 2,362 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

01,0002,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar6
Apr100
May223
Jun317
Jul435
Aug477
Sep395
Oct272
Nov126
Dec11

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.

Numazu receives about 4.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.5 and 5.5 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 10 to Sep 16. The brightest month is May, averaging about 5.4 kWh/m² (bright).

The dimmest month is December, down near 2.6 kWh/m² — roughly 53% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 235.5 kWhDec 32.5 kWh
Solar energy (kWh/m²)Level
Jan2.9Moderate
Feb3.5Moderate
Mar4.3Bright
Apr5.1Bright
May5.5Bright
Jun4.9Bright
Jul5.1Bright
Aug5.2Bright
Sep4.1Bright
Oct3.3Moderate
Nov2.7Moderate
Dec2.5Moderate

Where is Numazu?

Numazu sits at 35.1°N, 138.9°E, 8 m above sea level, in Japan. The nearest listed city is Fushimi, 3.0 km away.

Topography around Numazu

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

Within 3 km, the terrain around Numazu has significant variations in elevation — a maximum elevation change of 251 m around an average of 18 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,439 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,736 m.

The land around Numazu is covered by artificial surfaces (67%) within 3 km, trees (54%) and water (24%) within 16 km, and trees (46%) and water (42%) within 80 km.

3 km
251 m
16 km
1,439 m
80 km
3,736 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Fushimi 3.0 km · Mishima 5.0 km · Nakatogari 5.0 km · Kamizawa 8.0 km · Susono 9.0 km · Izunokuni 10 km · Shuzenji 15 km · Izu 16 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 Numazu (35.1°, 138.8667°, elevation 8 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).