Climate and average weather in Katsuta

In Katsuta, the summers are muggy, hot, showery, and partly cloudy and the winters are cold, snowy, and mostly clear.

Best: late April to mid November

Over the course of the year, the temperature in Katsuta typically varies from 2°C to 28°C, and is rarely below -1°C or above 32°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 Katsuta for warm-weather activities is from late April to mid November.

Hottest
Aug
28°
Coldest
Jan
Wettest
Oct
196 mm
Driest
Feb
63 mm
Rain / yr
1501 mm
141 wet days
Daylight
9.5–14.5 h
shortest–longest
Elevation
21 m
36.4°N
Clearest
Dec
41% cloud

Katsuta is dissolved municipality in Ibaraki prefecture, Japan.

Founded
1954

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

Katsuta 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 Katsuta, 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 19 to September 25, with daily high temperatures above 23°C. The hottest month of the year in Katsuta is August, with an average high of 28°C and low of 23°C.

The cool season lasts 3.5 months, from December 5 to March 20, with daily high temperatures below 12°C. The coldest month of the year in Katsuta is January, with an average low of 2°C and high of 8°C.

Days typically run about 6°C warmer than nights year-round.

10°20°30°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan82
Feb82
Mar114
Apr169
May2014
Jun2318
Jul2722
Aug2823
Sep2520
Oct2015
Nov159
Dec104

How hot and cold Katsuta 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 -2°C (around January 25), with roughly 65 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)
Jan88-12
Feb88-12
Mar111124
Apr161679
May20201414
Jun23231818
Jul28272222
Aug31282323
Sep25252020
Oct20201515
Nov151589
Dec101024

Average hourly temperature in Katsuta

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 28°C, and coldest before dawn in January, near C.

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

Katsuta 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 / 637.31.59.81.4
Feb / 637.3210.61.5
Mar11° / 11512.51.211.72.7
Apr16° / 12111.90.212.94.5
May20° / 14°14412.5013.95.8
Jun23° / 18°15114.7014.45.6
Jul27° / 22°17816014.25.4
Aug28° / 23°13114013.45.4
Sep25° / 20°17914.7012.25.8
Oct20° / 15°19612.7011.15.9
Nov15° / 989.5010.14.7
Dec10° / 647.60.39.62.6

Chance of rain

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

Katsuta gets about 1501 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 7.2 months, from around Mar 16 to Oct 20, peaking in July at about 57% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 1.

October is the wettest month by volume, with 196 mm over about 13 wet days; February is the driest, with 63 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJul 1 · 57%Jan 1 · 20%
Rain on a day (%)Rain days
Jan247
Feb287
Mar3913
Apr4012
May4013
Jun5015
Jul5116
Aug4614
Sep4915
Oct4013
Nov3210
Dec248

Monthly rainfall

Over a full year, Katsuta collects about 1501 mm of rain across 141 wet days — roughly 125 mm in an average month.

It doesn’t fall evenly. October is the wettest month with 196 mm, while February is the driest at just 63 mm. The three wettest months alone bring about 37% of the year’s total, and some of the cold-season precipitation falls as snow.

050100150200JanFebMarAprMayJunJulAugSepOctNovDec63631151211441511781311791969864
Rainfall (mm)Rain daysSnow days
Jan6372
Feb6372
Mar115131
Apr121120
May144130
Jun151150
Jul178160
Aug131140
Sep179150
Oct196130
Nov98100
Dec6480

Snow in Katsuta

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.

Katsuta averages about 5 snowy days a year. Snow season runs roughly Dec 31 to Apr 2 — about 3.1 months.

February is snowiest, with roughly 2 days of snow and an estimated 14 cm of snowfall. Over the year that adds up to an estimated 30 cm of snow.

01234JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonFeb 9
Snow daysSnowfall (cm)
Jan211
Feb214
Mar14
Apr00
May00
Jun00
Jul00
Aug00
Sep00
Oct00
Nov00
Dec01

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Katsuta, 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 20 and lasts for 5.6 months, ending around April 7. The clearest month is January, when the sky is clear, mostly clear, or partly cloudy 73% of the time on average.

The cloudier part of the year begins around April 8 and lasts for 6.4 months, ending around October 19. The cloudiest month is June, when it is overcast or mostly cloudy 79% 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 · 77%Jun 23 · 16%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan7327
Feb6238
Mar5248
Apr4555
May3862
Jun2179
Jul2575
Aug3763
Sep3664
Oct4555
Nov5842
Dec7030

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 14, brings about 14 h 30 min of light; the shortest, around December 14, 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)
Jan9.86:544:40
Feb10.66:345:11
Mar11.75:565:39
Apr12.95:106:06
May13.94:366:32
Jun14.44:246:52
Jul14.24:366:51
Aug13.45:006:24
Sep12.25:255:39
Oct11.15:514:55
Nov10.16:224:24
Dec9.66:484:20

Sunny days

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

Katsuta averages about 10 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 19 days.

The sunnier stretch runs 5.1 months, from around Oct 19 to Mar 22. The sunniest month is December, with roughly 17 sunny days (bright).

The greyest month is June, down near 3 sunny days — about 80% fewer than the December peak.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantDec 2919 daysJun 262 days
Sunny daysSky
Jan18Bright
Feb12Mixed
Mar10Mixed
Apr8Mixed
May7Gloomy
Jun3Gloomy
Jul4Gloomy
Aug6Gloomy
Sep6Gloomy
Oct9Mixed
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 Katsuta, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 4.4 months, from around May 30 to October 11. The muggiest month is August, when the air feels humid, muggy or worse about 99% of the time.

The most comfortable stretch runs from around October 12 to May 29, 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 30 · 100%Aug 7 · 0%miserablemuggycomfortablehumidoppressivedrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan10000000
Feb10000000
Mar10000000
Apr9451000
May543213100
Jun822372770
Jul031429468
Aug017205418
Sep6122429272
Oct492717610
Nov9271000
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 Katsuta is typically calm, near 10 km/h, and varies little with the seasons.

The windier part of the year lasts 5.2 months, from around Nov 29 to May 6. The windiest month is February, averaging about 12 km/h (calm).

The calmer part of the year runs from around May 7 to Sep 17, with July the calmest month at about 9 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezeFeb 25 · 12 km/hJul 21 · 9 km/h
Wind speed (km/h)Feels
Jan12calm
Feb12calm
Mar12calm
Apr11calm
May10calm
Jun9calm
Jul9calm
Aug9calm
Sep10calm
Oct11calm
Nov10calm
Dec11calm

Hazard calendar for Katsuta

In seasonPeak

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

Katsuta 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 Katsuta

TravelBeach/poolTemperatureCloudsPrecipitation

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

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

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationSep 26 · 6.0

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
Jan1.4poor
Feb1.5poor
Mar2.7poor
Apr4.5fair
May5.8good
Jun5.6good
Jul5.4fair
Aug5.4fair
Sep5.8good
Oct5.9good
Nov4.7fair
Dec2.6poor

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

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 5 · 6.3

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 Katsuta, 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 28°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 8°C), pack a warm layer and a heavy coat.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Katsuta sees daytime highs around 28°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 14 days see rain.

Sea temperature near Katsuta

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 24°C and coldest in February near 13°C.

It's comfortable for a long swim from Jun 24 to Oct 28 — about 4.2 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan15Bracing
Feb13Bracing
Mar13Bracing
Apr15Bracing
May17Cool
Jun19Cool
Jul22Refreshing
Aug24Warm
Sep23Refreshing
Oct21Refreshing
Nov19Cool
Dec16Cool

UV index (midday) in Katsuta 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 Katsuta peaks around July 24 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 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 highModerateJul 24UV 10Jan 1UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul10Very high
Aug10Very high
Sep8Very high
Oct6High
Nov3Moderate
Dec2Moderate

Average hourly UV index in Katsuta

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 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
Feb2.50
Mar4.50
Apr6.51.5
May7.54.5
Jun85
Jul8.55.5
Aug85.5
Sep74.5
Oct50
Nov1.50
Dec00

Air quality in Katsuta 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 Katsuta is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.5× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1821 µg/m³Dec 189 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar19Moderate
Apr21Moderate
May20Moderate
Jun16Moderate
Jul14Moderate
Aug13Moderate
Sep11Good
Oct11Good
Nov10Good
Dec9Good
Almanac & agriculture

Growing season

Chance of a frost-free dayReliably frost-free (≥90%)

Katsuta is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about February 28 to January 7 (314 days); outside that window a hard frost is an occasional risk.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecreliably frost-freeFeb 2890%Jan 790%
Frost-free chance (%)Frost nights
Jan8625
Feb8525
Mar950
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec960

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. Katsuta banks about 2,189 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
Apr65
May210
Jun315
Jul440
Aug484
Sep379
Oct231
Nov65
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.

Katsuta receives about 3.9 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 2.3 and 5.4 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 6 to Sep 12. The brightest month is May, averaging about 5.3 kWh/m² (bright).

The dimmest month is December, down near 2.4 kWh/m² — roughly 55% less than the May peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 255.4 kWhDec 52.3 kWh
Solar energy (kWh/m²)Level
Jan2.8Moderate
Feb3.5Moderate
Mar4.2Bright
Apr5.0Bright
May5.3Bright
Jun4.8Bright
Jul4.8Bright
Aug4.8Bright
Sep3.8Moderate
Oct3.0Moderate
Nov2.6Moderate
Dec2.4Moderate

Where is Katsuta?

Katsuta sits at 36.4°N, 140.5°E, 21 m above sea level, in Japan. The nearest listed city is Hitachi-Naka, 1.0 km away.

Topography around Katsuta

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

Within 3 km, the terrain around Katsuta has only modest variations in elevation — a maximum elevation change of 48 m around an average of 18 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 179 m; within 80 km, large variations in elevation — a maximum elevation change of 1,005 m.

The land around Katsuta is covered by artificial surfaces (53%) and cropland (26%) within 3 km, water (29%), artificial surfaces (25%) and cropland (23%) within 16 km, and trees (39%), water (26%) and cropland (21%) within 80 km.

3 km
48 m
16 km
179 m
80 km
1,005 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Hitachi-Naka 1.0 km · Inada 6.0 km · Mito 8.0 km · Ōarai 9.0 km · Funaishikawa 10 km · Tokai 10 km · Okunoya 15 km · Ishitsuka 17 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 Katsuta (36.3833°, 140.5333°, elevation 21 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).