Climate and average weather in Tateyama

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

Best: late June to mid November

Over the course of the year, the temperature in Tateyama typically varies from 8°C to 26°C, and is rarely below 4°C or above 28°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 Tateyama for warm-weather activities are from late April to mid June and late June to mid November.

Hottest
Aug
26°
Coldest
Jan
Wettest
Oct
241 mm
Driest
Dec
88 mm
Rain / yr
1755 mm
138 wet days
Daylight
9.6–14.4 h
shortest–longest
Elevation
7 m
35.0°N
Clearest
Dec
46% cloud

Tateyama is city in Chiba Prefecture, Japan.

Density
455/km²
people per km²
Founded
1939

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

Tateyama 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 June to mid November.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.5 months, from June 24 to October 8, with daily high temperatures above 23°C. The hottest month of the year in Tateyama is August, with an average high of 26°C and low of 25°C.

The cool season lasts 3.2 months, from December 14 to March 21, with daily high temperatures below 14°C. The coldest month of the year in Tateyama is January, with an average low of 8°C and high of 11°C.

Days typically run about 3°C warmer than nights year-round.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan118
Feb118
Mar1410
Apr1614
May1917
Jun2220
Jul2523
Aug2625
Sep2523
Oct2219
Nov1815
Dec1410

Average hourly temperature in Tateyama

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 C.

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

Tateyama weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan11° / 969.59.93.0
Feb11° / 969.910.72.9
Mar14° / 10°16214.111.73.6
Apr16° / 14°13511.612.95.0
May19° / 17°14810.913.86.0
Jun22° / 20°2101314.35.8
Jul25° / 23°14610.714.16.6
Aug26° / 25°100913.36.8
Sep25° / 23°19513.312.26.2
Oct22° / 19°24113.511.16.1
Nov18° / 15°13811.910.25.6
Dec14° / 10°8810.19.74.2

Chance of rain

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

Tateyama gets about 1755 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 1.1 months, from around Jun 6 to Jul 10, peaking in June at about 48% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 4.

October is the wettest month by volume, with 241 mm over about 14 wet days; December is the driest, with 88 mm.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJun 21 · 48%Aug 4 · 25%
Rain on a day (%)Rain days
Jan3110
Feb3610
Mar4414
Apr3912
May3511
Jun4413
Jul3411
Aug309
Sep4513
Oct4314
Nov4012
Dec3210

Monthly rainfall

Over a full year, Tateyama collects about 1755 mm of rain across 138 wet days — roughly 146 mm in an average month.

It doesn’t fall evenly. October is the wettest month with 241 mm, while December is the driest at just 88 mm. The three wettest months alone bring about 37% of the year’s total.

050100150200250300JanFebMarAprMayJunJulAugSepOctNovDec969616213514821014610019524113888
Rainfall (mm)Rain days
Jan9610
Feb9610
Mar16214
Apr13512
May14811
Jun21013
Jul14611
Aug1009
Sep19513
Oct24114
Nov13812
Dec8810

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Tateyama, 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 18 and lasts for 5.0 months, ending around March 19. The clearest month is December, when the sky is clear, mostly clear, or partly cloudy 65% of the time on average.

The cloudier part of the year begins around April 9 and lasts for 3.8 months, ending around August 1. The cloudiest month is June, when it is overcast or mostly cloudy 75% 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%JanFebMarAprMayJunJulAugSepOctNovDecJan 1 · 70%Jun 19 · 22%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan6337
Feb5644
Mar4951
Apr4753
May3961
Jun2575
Jul3466
Aug5347
Sep4654
Oct4852
Nov5644
Dec6535

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 20, brings about 14 h 24 min of light; the shortest, around December 19, 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)
Jan9.96:534:46
Feb10.76:345:16
Mar11.75:585:42
Apr12.95:146:07
May13.84:426:32
Jun14.34:316:51
Jul14.14:426:50
Aug13.35:056:24
Sep12.25:285:41
Oct11.15:524:59
Nov10.26:224:30
Dec9.76:474:26

Sunny days

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

Tateyama averages about 11 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 4 and 16 days.

The sunnier stretch runs 4.2 months, from around Oct 17 to Feb 21. The sunniest month is January, with roughly 14 sunny days (mixed).

The greyest month is June, down near 5 sunny days — about 66% fewer than the January peak.

05101520JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightJan 116 daysJun 214 days
Sunny daysSky
Jan14Mixed
Feb11Mixed
Mar11Mixed
Apr11Mixed
May9Mixed
Jun5Gloomy
Jul8Gloomy
Aug13Mixed
Sep10Mixed
Oct11Mixed
Nov13Mixed
Dec15Mixed

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

The more humid part of the year lasts 5.1 months, from around May 16 to October 18. The muggiest month is July, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around October 19 to May 15, and January 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%JanFebMarAprMayJunJulAugSepOctNovDecJan 29 · 100%Jul 15 · 0%miserableoppressivehumidmuggydrycomfortablecomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb9910000
Mar9640000
Apr71226000
May233435800
Jun193045140
Jul004215420
Aug002103850
Sep2715293315
Oct2330251740
Nov73188100
Dec9720000

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 Tateyama is typically breezy, near 24 km/h, and varies moderately with the seasons.

The windier part of the year lasts 7.1 months, from around Sep 25 to Apr 29. The windiest month is March, averaging about 26 km/h (breezy).

The calmer part of the year runs from around Apr 30 to Sep 24, with June the calmest month at about 21 km/h.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezywindyMar 12 · 27 km/hJun 5 · 20 km/h
Wind speed (km/h)Feels
Jan26breezy
Feb26breezy
Mar26breezy
Apr25breezy
May22breezy
Jun21breezy
Jul21breezy
Aug20breezy
Sep22breezy
Oct25breezy
Nov25breezy
Dec26breezy

Hazard calendar for Tateyama

In seasonPeak

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

Tateyama 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 Tateyama

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around early November, Tateyama is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

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 Tateyama for general outdoor tourist activities is from late April to mid November, with a peak score in the first week of August.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationAug 3 · 7.0

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
Jan3.0poor
Feb2.9poor
Mar3.6fair
Apr5.0fair
May6.0good
Jun5.8good
Jul6.6good
Aug6.8good
Sep6.2good
Oct6.1good
Nov5.6good
Dec4.2fair

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 Tateyama for hot-weather activities is from mid July to late September, with a peak score in the second week of August.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 9 · 6.8

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 Tateyama, 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, sun protection and a windbreaker. In the cold season around January (highs near 11°C), pack a warm layer, rain gear and a windbreaker.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Tateyama sees daytime highs around 26°C and nights near 25°C. Worth packing: light clothes, rain gear, sun protection and a windbreaker. About 9 days see rain.

Sea temperature near Tateyama

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

The sea offshore is warmest in August at about 26°C and coldest in February near 16°C.

It's comfortable for a long swim from May 25 to Dec 4 — about 6.4 months when the water holds above 20°C.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan17Cool
Feb16Cool
Mar16Cool
Apr17Cool
May19Cool
Jun22Refreshing
Jul24Refreshing
Aug26Warm
Sep26Warm
Oct24Refreshing
Nov22Refreshing
Dec19Cool

UV index (midday) in Tateyama 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 Tateyama peaks around August 10 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateAug 10UV 10Dec 23UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May9Very high
Jun10Very high
Jul10Extreme
Aug10Extreme
Sep8Very high
Oct6High
Nov4Moderate
Dec3Moderate

Average hourly UV index in Tateyama

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 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
Feb3.50
Mar50
Apr6.53
May85
Jun8.55.5
Jul8.56
Aug86
Sep74.5
Oct5.50
Nov30
Dec00

Air quality in Tateyama 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 Tateyama is worst in April — around 26 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (December, 12 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateApr 1525 µg/m³Dec 1612 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb25Moderate
Mar23Moderate
Apr26Moderate
May21Moderate
Jun18Moderate
Jul13Moderate
Aug12Moderate
Sep12Moderate
Oct14Moderate
Nov14Moderate
Dec12Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Tateyama 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
Feb1000
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. Tateyama banks about 2,711 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

01,0002,0003,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan1
Feb0
Mar49
Apr149
May257
Jun333
Jul435
Aug488
Sep423
Oct321
Nov191
Dec64

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.

Tateyama receives about 4.0 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.3 and 5.6 kWh/m².

The brighter stretch of the year lasts 6.1 months, from around Mar 15 to Sep 17. The brightest month is August, averaging about 5.3 kWh/m² (bright).

The dimmest month is December, down near 2.4 kWh/m² — roughly 56% less than the August peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseAug 35.6 kWhDec 42.3 kWh
Solar energy (kWh/m²)Level
Jan2.7Moderate
Feb3.3Moderate
Mar4.0Bright
Apr5.0Bright
May5.4Bright
Jun4.9Bright
Jul5.3Bright
Aug5.4Bright
Sep4.1Bright
Oct3.1Moderate
Nov2.5Moderate
Dec2.3Moderate

Where is Tateyama?

Tateyama sits at 35.0°N, 139.9°E, 7 m above sea level, in Japan. The nearest listed city is Minamibōsō, 8.0 km away.

Topography around Tateyama

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

Within 3 km, the terrain around Tateyama has only modest variations in elevation — a maximum elevation change of 159 m around an average of 31 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 354 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,372 m.

The land around Tateyama is covered by trees (45%) and artificial surfaces (26%) within 3 km, water (59%) and trees (32%) within 16 km, and water (66%) within 80 km.

3 km
159 m
16 km
354 m
80 km
1,372 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Minamibōsō 8.0 km · Kamogawa 25 km · Miura 28 km · Kurihama 31 km · Futtsu 37 km · Yokosuka 38 km · Kimitsu 41 km · Hayama 42 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 Tateyama (34.9833°, 139.8667°, elevation 7 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).