Climate and average weather in Saikū

In Saikū, the summers are muggy, hot, showery, and partly cloudy and the winters are cool and mostly clear.

Best: early April to late June

Over the course of the year, the temperature in Saikū typically varies from 5°C to 30°C, and is rarely below 2°C or above 34°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 Saikū for warm-weather activities are from early April to late June and mid September to late November.

Hottest
Aug
30°
Coldest
Jan
Wettest
Oct
254 mm
Driest
Jan
70 mm
Rain / yr
1819 mm
130 wet days
Daylight
9.7–14.3 h
shortest–longest
Elevation
10 m
34.5°N
Clearest
Dec
38% cloud

Saikū 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 early April to late June.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.3 months, from June 18 to September 26, with daily high temperatures above 25°C. The hottest month of the year in Saikū is August, with an average high of 30°C and low of 25°C.

The cool season lasts 3.3 months, from December 6 to March 16, with daily high temperatures below 14°C. The coldest month of the year in Saikū is January, with an average low of 5°C and high of 10°C.

Days typically run about 5°C warmer than nights year-round.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan105
Feb115
Mar147
Apr1812
May2216
Jun2520
Jul2924
Aug3025
Sep2722
Oct2217
Nov1712
Dec127

How hot and cold Saikū 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, Saikū feels like about 36°C (around August 7). About 54 days a year carry some heat stress, peaking in August.

10°20°30°40°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan101015
Feb111115
Mar141447
Apr18181112
May22221616
Jun25252020
Jul33292424
Aug35302525
Sep29272222
Oct22221717
Nov17171212
Dec121247

Average hourly temperature in Saikū

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 C.

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

Saikū 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
Jan10° / 705.9102.5
Feb11° / 72710.72.8
Mar14° / 12610.411.74.1
Apr18° / 12°1371012.85.8
May22° / 16°16411.813.86.4
Jun25° / 20°2351514.35.6
Jul29° / 24°19114.514.14.7
Aug30° / 25°14413.613.34.4
Sep27° / 22°24715.312.25.4
Oct22° / 17°25412.311.16.5
Nov17° / 12°1108.210.25.9
Dec12° / 706.49.73.8

Chance of rain

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

Saikū gets about 1819 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 5.7 months, from around May 2 to Oct 21, peaking in June at about 57% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 2.

October is the wettest month by volume, with 254 mm over about 12 wet days; January is the driest, with 70 mm.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJun 25 · 57%Jan 2 · 17%
Rain on a day (%)Rain days
Jan206
Feb257
Mar3310
Apr3410
May3712
Jun5015
Jul4615
Aug4414
Sep5115
Oct3912
Nov288
Dec206

Monthly rainfall

Over a full year, Saikū collects about 1819 mm of rain across 130 wet days — roughly 152 mm in an average month.

It doesn’t fall evenly. October is the wettest month with 254 mm, while January is the driest at just 70 mm. The three wettest months alone bring about 40% of the year’s total.

050100150200250300JanFebMarAprMayJunJulAugSepOctNovDec707212613716423519114424725411070
Rainfall (mm)Rain days
Jan706
Feb727
Mar12610
Apr13710
May16412
Jun23515
Jul19115
Aug14414
Sep24715
Oct25412
Nov1108
Dec706

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Saikū, 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 5.8 months, ending around April 7. The clearest month is December, when the sky is clear, mostly clear, or partly cloudy 74% of the time on average.

The cloudier part of the year begins around April 8 and lasts for 6.2 months, ending around October 12. 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 · 79%Jun 23 · 18%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan7030
Feb6436
Mar5545
Apr4951
May3961
Jun2278
Jul3169
Aug4852
Sep4456
Oct5347
Nov6436
Dec7426

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 10, brings about 14 h 18 min of light; the shortest, around January 1, only 9 h 42 min — a swing of roughly 4 h 36 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.07:055:00
Feb10.76:475:29
Mar11.76:115:55
Apr12.85:286:20
May13.84:566:44
Jun14.34:457:03
Jul14.14:567:02
Aug13.35:186:37
Sep12.25:415:54
Oct11.16:055:12
Nov10.26:344:44
Dec9.76:594:41

Sunny days

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

Saikū 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 5.7 months, from around Oct 8 to Mar 31. The sunniest month is December, with roughly 18 sunny days (bright).

The greyest month is June, down near 4 sunny days — about 80% fewer than the December peak.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantDec 2719 daysJun 223 days
Sunny daysSky
Jan17Bright
Feb12Mixed
Mar12Mixed
Apr11Mixed
May8Mixed
Jun4Gloomy
Jul6Gloomy
Aug10Mixed
Sep9Mixed
Oct13Mixed
Nov15Bright
Dec19Bright

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

The more humid part of the year lasts 4.8 months, from around May 22 to October 14. 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 15 to May 21, and February 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%JanFebMarAprMayJunJulAugSepOctNovDecFeb 24 · 100%Jul 10 · 0%miserablehumidcomfortablemuggyoppressivedrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb10000000
Mar9820000
Apr80154100
May363225700
Jun4102837192
Jul002185227
Aug012114442
Sep4817293111
Oct3628221130
Nov81144100
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 Saikū is typically light breeze, near 15 km/h, and varies moderately with the seasons.

The windier part of the year lasts 5.5 months, from around Nov 11 to Apr 25. The windiest month is January, averaging about 18 km/h (light breeze).

The calmer part of the year runs from around Apr 26 to Nov 10, with July the calmest month at about 11 km/h.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezyJan 29 · 19 km/hJul 14 · 11 km/h
Wind speed (km/h)Feels
Jan18light breeze
Feb18light breeze
Mar17light breeze
Apr15light breeze
May13light breeze
Jun11calm
Jul11calm
Aug11calm
Sep13light breeze
Oct14light breeze
Nov15light breeze
Dec17light breeze

Hazard calendar for Saikū

In seasonPeak

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

Saikū 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 Saikū

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around mid April, Saikū 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 Saikū for general outdoor tourist activities run from early April to late June and again from mid September to late November, with a peak score in the third week of October.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationOct 17 · 6.5

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
Jan2.6poor
Feb2.8poor
Mar4.1fair
Apr5.8good
May6.3good
Jun5.6good
Jul4.7fair
Aug4.5fair
Sep5.4fair
Oct6.4good
Nov5.9good
Dec3.9fair

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

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 3 · 6.4

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 Saikū, 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 10°C), pack a warm layer.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Saikū sees daytime highs around 30°C and nights near 25°C. Pack light clothes. Worth having: rain gear and sun protection. About 14 days see rain.

Sea temperature near Saikū

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 27°C and coldest in February near 14°C.

It's comfortable for a long swim from May 31 to Nov 11 — about 5.4 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan14Bracing
Feb14Bracing
Mar14Bracing
Apr15Cool
May19Cool
Jun22Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov20Cool
Dec17Cool

UV index (midday) in Saikū 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 Saikū peaks around July 13 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 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 highModerateJul 13UV 10Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7High
May8Very high
Jun10Very high
Jul10Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Average hourly UV index in Saikū

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
Feb3.50
Mar50
Apr6.53
May84.5
Jun8.55.5
Jul8.56
Aug85
Sep7.54.5
Oct5.50
Nov30
Dec00

Air quality in Saikū 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 Saikū is worst in March — around 26 µg/m³ PM2.5 (moderate), about 1.6× the cleanest month (July, 16 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 2326 µg/m³Jul 2316 µg/m³
PM2.5 (µg/m³)Level
Jan19Moderate
Feb21Moderate
Mar26Moderate
Apr26Moderate
May24Moderate
Jun20Moderate
Jul16Moderate
Aug16Moderate
Sep17Moderate
Oct19Moderate
Nov21Moderate
Dec18Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Saikū 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
Jan990
Feb980
Mar990
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. Saikū banks about 2,805 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)
Jan0
Feb0
Mar22
Apr148
May285
Jun384
Jul517
Aug551
Sep445
Oct303
Nov137
Dec12

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.

Saikū receives about 4.3 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.6 and 5.7 kWh/m².

The brighter stretch of the year lasts 6.4 months, from around Mar 8 to Sep 17. The brightest month is August, averaging about 5.5 kWh/m² (bright).

The dimmest month is December, down near 2.7 kWh/m² — roughly 52% less than the August peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseAug 25.7 kWhDec 102.6 kWh
Solar energy (kWh/m²)Level
Jan3.0Moderate
Feb3.7Moderate
Mar4.6Bright
Apr5.4Bright
May5.7Bright
Jun5.2Bright
Jul5.4Bright
Aug5.6Bright
Sep4.4Bright
Oct3.5Moderate
Nov2.9Moderate
Dec2.6Moderate

Where is Saikū?

Saikū sits at 34.5°N, 136.6°E, 10 m above sea level, in Japan. The nearest listed city is Tamaru, 6.0 km away.

Topography around Saikū

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

Within 3 km, the terrain around Saikū has only modest variations in elevation — a maximum elevation change of 64 m around an average of 13 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 604 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,887 m.

The land around Saikū is covered by cropland (50%) and artificial surfaces (26%) within 3 km, trees (34%) and water (33%) within 16 km, and trees (42%) and water (38%) within 80 km.

3 km
64 m
16 km
604 m
80 km
1,887 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Tamaru 6.0 km · Ise 8.0 km · Matsusaka 10 km · Toba 20 km · Hisai-motomachi 21 km · Tsu 25 km · Shima 29 km · Kawage 31 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 Saikū (34.5333°, 136.6333°, elevation 10 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).