Climate and average weather in Unnan

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

Best: mid April to late June

Over the course of the year, the temperature in Unnan typically varies from 0°C to 30°C, and is rarely below -4°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 Unnan for warm-weather activities are from mid April to late June and early September to early November.

Hottest
Aug
30°
Coldest
Jan
Wettest
Jul
229 mm
Driest
Nov
94 mm
Rain / yr
1681 mm
167 wet days
Daylight
9.6–14.4 h
shortest–longest
Elevation
82 m
35.2°N
Clearest
Oct
57% cloud

Unnan 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 mid April to late June.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Unnan, 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 10 to September 22, with daily high temperatures above 24°C. The hottest month of the year in Unnan is August, with an average high of 30°C and low of 23°C.

The cool season lasts 3.2 months, from December 5 to March 12, with daily high temperatures below 11°C. The coldest month of the year in Unnan is January, with an average low of 0°C and high of 7°C.

Days typically run about 8°C warmer than nights year-round.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan70
Feb80
Mar123
Apr178
May2213
Jun2518
Jul2922
Aug3023
Sep2618
Oct2012
Nov157
Dec92

How hot and cold Unnan 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, Unnan feels like about 34°C (around August 3). About 32 days a year carry some heat stress, peaking in August.

On the coldest nights, wind chill pulls the feels-like down to about -5°C (around January 27), with roughly 100 freezing days a year (feels-like at or below 0°C), worst in January.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan67-40
Feb88-40
Mar121203
Apr171768
May22221313
Jun25251718
Jul31292222
Aug33302323
Sep26261818
Oct20201212
Nov151557
Dec99-12

Average hourly temperature in Unnan

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

Unnan 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 / 1071710.39.90.6
Feb / 10014.88.410.71.0
Mar12° / 12814.93.211.72.7
Apr17° / 11711.40.212.95.3
May22° / 13°12811013.86.4
Jun25° / 18°17514.4014.35.8
Jul29° / 22°22916.6014.14.6
Aug30° / 23°16115.1013.34.4
Sep26° / 18°21314.1012.25.9
Oct20° / 12°11610.6011.16.3
Nov15° / 9411.20.310.14.3
Dec / 11416.36.19.71.6

Chance of rain

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

Unnan gets about 1681 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 1.5 months, from around Jun 14 to Jul 28, peaking in July at about 61% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Oct 19.

July is the wettest month by volume, with 229 mm over about 17 wet days; November is the driest, with 94 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJul 2 · 61%Oct 19 · 32%
Rain on a day (%)Rain days
Jan5517
Feb5315
Mar4815
Apr3811
May3511
Jun4814
Jul5317
Aug4915
Sep4614
Oct3511
Nov3811
Dec5216

Monthly rainfall

Over a full year, Unnan collects about 1681 mm of rain across 167 wet days — roughly 140 mm in an average month.

It doesn’t fall evenly. July is the wettest month with 229 mm, while November is the driest at just 94 mm. The three wettest months alone bring about 37% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200250JanFebMarAprMayJunJulAugSepOctNovDec10710012811712817522916121311694114
Rainfall (mm)Rain daysSnow days
Jan1071710
Feb100158
Mar128153
Apr117110
May128110
Jun175140
Jul229170
Aug161150
Sep213140
Oct116110
Nov94110
Dec114166

Snow in Unnan

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.

Unnan averages about 29 snowy days a year. Snow season runs roughly Nov 21 to Apr 8 — about 4.6 months.

January is snowiest, with roughly 10 days of snow and an estimated 47 cm of snowfall. Over the year that adds up to an estimated 139 cm of snow.

051015JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonJan 30
Snow daysSnowfall (cm)
Jan1047
Feb846
Mar314
Apr01
May00
Jun00
Jul00
Aug00
Sep00
Oct00
Nov01
Dec630

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Unnan, 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 September 8 and lasts for 3.2 months, ending around December 12. The clearest month is October, when the sky is clear, mostly clear, or partly cloudy 49% of the time on average.

The cloudier part of the year begins around May 26 and lasts for 2.0 months, ending around July 25. 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%JanFebMarAprMayJunJulAugSepOctNovDecOct 27 · 54%Jun 30 · 18%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearer
Clearer (%)Cloudier (%)
Jan3169
Feb3070
Mar4060
Apr4456
May4060
Jun2575
Jul2971
Aug4159
Sep3961
Oct4951
Nov4852
Dec3862

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 15, brings about 14 h 24 min of light; the shortest, around December 14, 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)
Jan9.97:225:14
Feb10.77:035:43
Mar11.76:266:10
Apr12.95:426:35
May13.85:097:00
Jun14.34:587:19
Jul14.15:097:19
Aug13.35:326:53
Sep12.25:566:09
Oct11.16:215:26
Nov10.16:504:57
Dec9.77:154:54

Sunny days

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

Unnan averages about 6 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 11 days.

The sunnier stretch runs 4.2 months, from around Jul 24 to Nov 28. The sunniest month is October, with roughly 10 sunny days (mixed).

The greyest month is January, down near 2 sunny days — about 75% fewer than the October peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedOct 1911 daysJan 192 days
Sunny daysSky
Jan3Gloomy
Feb3Gloomy
Mar7Gloomy
Apr9Mixed
May9Mixed
Jun4Gloomy
Jul5Gloomy
Aug8Gloomy
Sep7Gloomy
Oct10Mixed
Nov8Gloomy
Dec4Gloomy

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

The more humid part of the year lasts 4.0 months, from around June 5 to October 4. 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 5 to June 4, 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 25 · 100%Jul 30 · 0%oppressivedryhumidcomfortablemuggycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb10000000
Mar10000000
Apr9451000
May68228100
Jun1427312170
Jul011038501
Aug01630612
Sep10192629170
Oct642210400
Nov9451000
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 Unnan is typically calm, near 11 km/h, and varies little with the seasons.

The windier part of the year lasts 6.0 months, from around Nov 12 to May 12. The windiest month is January, averaging about 12 km/h (light breeze).

The calmer part of the year runs from around May 13 to Nov 11, with June the calmest month at about 9 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezeJan 1 · 12 km/hJun 10 · 9 km/h
Wind speed (km/h)Feels
Jan12light breeze
Feb12calm
Mar12calm
Apr11calm
May10calm
Jun9calm
Jul10calm
Aug9calm
Sep10calm
Oct10calm
Nov11calm
Dec12calm

Hazard calendar for Unnan

In seasonPeak

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

Unnan 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 Unnan

TravelBeach/poolTemperatureCloudsPrecipitation

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

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

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMay 28 · 6.6

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
Jan0.6poor
Feb1.0poor
Mar2.7poor
Apr5.2fair
May6.4good
Jun5.8good
Jul4.6fair
Aug4.4fair
Sep5.8good
Oct6.3good
Nov4.3fair
Dec1.7poor

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 Unnan for hot-weather activities is from late May to early October, with a peak score in the last week of July.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationJul 30 · 6.1

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 Unnan, 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 7°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Unnan sees daytime highs around 30°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 15 days see rain.

Sea temperature near Unnan

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 29 km away) is warmest in August at about 27°C and coldest in February near 13°C.

It's comfortable for a long swim from Jun 12 to Nov 15 — about 5.2 months when the water holds above 20°C.

10°15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb13Bracing
Mar13Bracing
Apr15Bracing
May17Cool
Jun21Refreshing
Jul24Warm
Aug27Warm
Sep25Warm
Oct23Refreshing
Nov20Refreshing
Dec17Cool

UV index (midday) in Unnan 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 Unnan peaks around July 18 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 18UV 10Dec 23UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May8Very high
Jun9Very high
Jul11Extreme
Aug10Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec2Moderate

Average hourly UV index in Unnan

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
Aug85.5
Sep7.54.5
Oct5.50
Nov30
Dec00

Air quality in Unnan 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 Unnan is worst in April — around 22 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (October, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodApr 1222 µg/m³Oct 1310 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb16Moderate
Mar21Moderate
Apr22Moderate
May20Moderate
Jun17Moderate
Jul13Moderate
Aug12Good
Sep11Good
Oct10Good
Nov12Good
Dec11Good
Almanac & agriculture

Growing season

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

The growing season in Unnan typically lasts about 333 days, from around February 16 to January 14 — the span where a frost-free day is more likely than not. It is reliably frost-free from March 30 to December 4.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecgrowing seasonFeb 1650%Mar 3090%Dec 490%Jan 1450%
Frost-free chance (%)Frost nights
Jan5031
Feb5028
Mar7929
Apr970
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov980
Dec7926

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. Unnan banks about 2,218 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
Apr76
May228
Jun337
Jul477
Aug506
Sep361
Oct196
Nov37
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.

Unnan receives about 4.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.1 and 5.8 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 11 to Sep 19. The brightest month is May, averaging about 5.7 kWh/m² (bright).

The dimmest month is December, down near 2.1 kWh/m² — roughly 63% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 245.8 kWhDec 132.1 kWh
Solar energy (kWh/m²)Level
Jan2.4Moderate
Feb3.2Moderate
Mar4.2Bright
Apr5.3Bright
May5.7Bright
Jun5.3Bright
Jul5.2Bright
Aug5.2Bright
Sep4.2Bright
Oct3.5Moderate
Nov2.5Moderate
Dec2.1Moderate

Where is Unnan?

Unnan sits at 35.2°N, 132.9°E, 82 m above sea level, in Japan. The nearest listed city is Izumo, 18 km away.

Topography around Unnan

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

Within 3 km, the terrain around Unnan has significant variations in elevation — a maximum elevation change of 398 m around an average of 240 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,049 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,623 m.

The land around Unnan is covered by trees (94%) within 3 km, trees (92%) within 16 km, and trees (60%) and water (35%) within 80 km.

3 km
398 m
16 km
1,049 m
80 km
1,623 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Izumo 18 km · Hiratachō 22 km · Matsue 30 km · Ōdachō-ōda 36 km · Yasugichō 37 km · Sakaiminato 44 km · Yonago 45 km · Shōbara 45 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 Unnan (35.2431°, 132.8999°, elevation 82 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).