Climate and average weather in Demak

In Demak, the weather is humid, sweltering, wet, and partly cloudy and remarkably steady, with daytime highs holding near sweltering levels all year. The wettest stretch peaks around December.

Best: mid May to mid September

Over the course of the year, the temperature in Demak typically varies from 23°C to 34°C, and is rarely below 21°C or above 37°C. September is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Demak for warm-weather activities is from mid May to mid September.

Hottest
Sep
34°
Coldest
Jan
24°
Wettest
Dec
351 mm
Driest
Aug
17 mm
Rain / yr
2113 mm
215 wet days
Daylight
11.6–12.4 h
shortest–longest
Elevation
9 m
6.9°S
Clearest
Aug
51% cloud

Demak is capital of Demak Regency, Central Java Province, Indonesia.

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

Demak 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 May to mid September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

Temperatures in Demak stay fairly even through the year, without a distinct hot or cool season. The warmest month is September, with an average high of 34°C and low of 24°C; the coolest is January, with an average low of 24°C and high of 31°C.

Days typically run about 9°C warmer than nights, with the widest day–night swing (around 10°C) in September.

20°25°30°35°40°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan3124
Feb3124
Mar3224
Apr3224
May3224
Jun3324
Jul3323
Aug3323
Sep3424
Oct3424
Nov3324
Dec3224

How hot and cold Demak 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, Demak feels like about 40°C (around April 11). Nearly every day a year carries some heat stress, and 114 of them tip into dangerous heat (feels-like above 39°C), peaking in April.

20°25°30°35°40°45°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan37312424
Feb37312424
Mar39322424
Apr40322424
May39322424
Jun37332424
Jul36332323
Aug36332323
Sep37342424
Oct39342424
Nov40332424
Dec39322424

Average hourly temperature in Demak

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 September afternoons, near 34°C, and coldest before dawn in January, near 24°C.

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

Demak 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
Jan31° / 24°33929.112.42.5
Feb31° / 24°31226.412.22.4
Mar32° / 24°30728.5122.3
Apr32° / 24°21325.211.92.4
May32° / 24°9415.811.73.3
Jun33° / 24°559.811.63.7
Jul33° / 23°315.411.63.9
Aug33° / 23°173.511.83.8
Sep34° / 24°355.1123.2
Oct34° / 24°11613.612.22.6
Nov33° / 24°24324.112.32.1
Dec32° / 24°35128.312.42.3

Chance of rain

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

Demak gets about 2113 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 6.3 months, from around Oct 29 to May 7, peaking in February at about 96% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Aug 5.

December is the wettest month by volume, with 351 mm over about 28 wet days; August is the driest, with 17 mm.

0%10%20%30%40%50%60%70%80%90%100%110%JanFebMarAprMayJunJulAugSepOctNovDecwetterdrierwettermostly drysome rainoften wetvery wetFeb 1 · 96%Aug 5 · 10%
Rain on a day (%)Rain days
Jan9429
Feb9426
Mar9229
Apr8325
May5116
Jun3310
Jul175
Aug114
Sep185
Oct4414
Nov7924
Dec9128

Monthly rainfall

Over a full year, Demak collects about 2113 mm of rain across 215 wet days — roughly 176 mm in an average month.

It doesn’t fall evenly. December is the wettest month with 351 mm, while August is the driest at just 17 mm. The three wettest months alone bring about 47% of the year’s total.

050100150200250300350400JanFebMarAprMayJunJulAugSepOctNovDec3393123072139455311735116243351
Rainfall (mm)Rain days
Jan33929
Feb31226
Mar30729
Apr21325
May9416
Jun5510
Jul315
Aug174
Sep355
Oct11614
Nov24324
Dec35128

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Demak, 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 May 1 and lasts for 5.8 months, ending around October 23. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 64% of the time on average.

The cloudier part of the year begins around October 24 and lasts for 6.2 months, ending around April 30. The cloudiest month is February, when it is overcast or mostly cloudy 96% 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%JanFebMarAprMayJunJulAugSepOctNovDecAug 6 · 65%Feb 5 · 4%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan793
Feb496
Mar1288
Apr2377
May4654
Jun5545
Jul6040
Aug6436
Sep5644
Oct3763
Nov1882
Dec793

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 January 1, brings about 12 h 24 min of light; the shortest, around May 26, only 11 h 36 min — a swing of roughly 0 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan12.45:365:58
Feb12.25:455:59
Mar12.05:465:49
Apr11.95:425:33
May11.75:435:24
Jun11.65:505:26
Jul11.65:545:32
Aug11.85:485:35
Sep12.05:335:31
Oct12.25:185:27
Nov12.35:135:32
Dec12.45:225:46

Sunny days

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

Demak averages about 5 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 0 and 12 days.

The sunnier stretch runs 5.5 months, from around May 5 to Oct 19. The sunniest month is August, with roughly 11 sunny days (mixed).

The greyest month is February, down near 0 sunny days — about 98% fewer than the August peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedAug 612 daysFeb 50 days
Sunny daysSky
Jan0Gloomy
Feb0Gloomy
Mar1Gloomy
Apr3Gloomy
May8Gloomy
Jun10Mixed
Jul11Mixed
Aug12Mixed
Sep9Mixed
Oct6Gloomy
Nov2Gloomy
Dec0Gloomy

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.

Demak is humid all year round — on a typical day the air feels at least humid, and there is no real dry season to wait for.

The stickiest month is January, when it feels muggy, oppressive or miserable about 100% of the time. Even in January, the mildest month, the air is dry or comfortable only 0% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecmiserablemuggyoppressivehumid
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan003466
Feb003466
Mar002674
Apr001882
May034057
Jun1185426
Jul745408
Aug1157293
Sep656335
Oct1305217
Nov034948
Dec003169

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 Demak is typically calm, near 6 km/h, and varies little with the seasons.

The windier part of the year lasts 2.0 months, from around Jan 4 to Mar 5. The windiest month is February, averaging about 7 km/h (calm).

The calmer part of the year runs from around Mar 6 to Jun 21, with April the calmest month at about 4 km/h.

051015JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmercalmlight breezeFeb 2 · 8 km/hApr 6 · 4 km/h
Wind speed (km/h)Feels
Jan7calm
Feb7calm
Mar5calm
Apr4calm
May5calm
Jun6calm
Jul6calm
Aug7calm
Sep7calm
Oct6calm
Nov5calm
Dec5calm

Hazard calendar for Demak

In seasonPeak

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

Demak sits in the South Indian Ocean cyclone belt; the season peaks January–March.

Demak's monsoon runs November–April, when most of the year's rain falls.

Cyclone
Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Best time to visit Demak

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around late May, Demak 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 Demak for general outdoor tourist activities is from mid May to mid September, with a peak score in the last week of July.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJul 29 · 4.0

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
Jan2.5poor
Feb2.4poor
Mar2.3poor
Apr2.4poor
May3.3poor
Jun3.7fair
Jul3.9fair
Aug3.8fair
Sep3.2poor
Oct2.6poor
Nov2.1poor
Dec2.3poor

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

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationAug 5 · 7.2

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 Demak, 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.

Demak packs about the same all year — highs hold near 34°C. Across the year the things worth having are light clothes, sun protection and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In September, Demak sees daytime highs around 34°C and nights near 24°C. Pack light clothes and sun protection. About 5 days see rain.

Sea temperature near Demak

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 May at about 30°C and coldest in February near 29°C.

The water stays above 20°C all year — warm enough for a swim any month.

28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr30Tropical
May30Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov30Tropical
Dec30Tropical

UV index (midday) in Demak 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 Demak peaks around March 15 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 16 at about 7 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeVery highExtremeMar 15UV 14Nov 16UV 7
UV index (midday)Level
Jan10Extreme
Feb12Extreme
Mar14Extreme
Apr11Extreme
May8Very high
Jun8Very high
Jul9Very high
Aug11Extreme
Sep12Extreme
Oct11Extreme
Nov7High
Dec12Extreme

Average hourly UV index in Demak

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 March the burn window is concentrated in the middle of the day: about 8 hours a day reach index 3 (protection recommended), and 6.5 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)
Jan85.5
Feb86
Mar86.5
Apr7.55.5
May74
Jun6.53.5
Jul74.5
Aug7.55.5
Sep86
Oct7.55.5
Nov6.53
Dec86

Air quality in Demak 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 Demak is worst in May — around 45 µg/m³ PM2.5 (poor), and holds fairly steady the rest of the year.

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateMay 1944 µg/m³Feb 1129 µg/m³
PM2.5 (µg/m³)Level
Jan31Moderate
Feb29Moderate
Mar35Poor
Apr39Poor
May45Poor
Jun42Poor
Jul38Poor
Aug35Poor
Sep37Poor
Oct39Poor
Nov37Poor
Dec34Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Demak 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. Demak banks about 6,650 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around October.

02,0004,0006,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan538
Feb487
Mar555
Apr547
May566
Jun542
Jul559
Aug566
Sep570
Oct599
Nov565
Dec555

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.

Demak receives about 5.4 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 4.7 and 6.5 kWh/m².

The brighter stretch of the year lasts 4.1 months, from around Jul 21 to Nov 22. The brightest month is September, averaging about 6.4 kWh/m² (intense).

The dimmest month is January, down near 4.8 kWh/m² — roughly 25% less than the September peak.

012345678JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseSep 236.5 kWhJan 294.7 kWh
Solar energy (kWh/m²)Level
Jan4.8Bright
Feb4.9Bright
Mar5.2Bright
Apr5.3Bright
May5.2Bright
Jun5.0Bright
Jul5.3Bright
Aug6.0Bright
Sep6.5Intense
Oct6.3Intense
Nov5.6Bright
Dec5.0Bright

Where is Demak?

Demak sits at 6.9°S, 110.6°E, 9 m above sea level, in Indonesia. The nearest listed city is Welahan, 13 km away.

Topography around Demak

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

Within 3 km, the terrain around Demak has only modest variations in elevation — a maximum elevation change of 10 m around an average of 4 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 20 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,105 m.

The land around Demak is covered by cropland (58%) and artificial surfaces (22%) within 3 km, cropland (63%) within 16 km, and trees (39%), water (31%) and cropland (21%) within 80 km.

3 km
10 m
16 km
20 m
80 km
3,105 m
treesgrasslandcroplandartificial surfaceswaterwetlandmangroves
Nearby: Welahan 13 km · Mranggen 20 km · Pecangaan 23 km · Kudus 24 km · Semarang 27 km · Baekrajan 27 km · Gebog 28 km · Jekulo 33 km

Indonesia travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 29% of US
price level, 2025
GDP per capita
$5,060
2025
Happiness
5.6 / 10
World Happiness, 2025
Safe drinking water
30%
of population, 2024
Homicide rate
0.3
per 100k, 2022
Road deaths
11.3
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 471
Religion
Muslim 87%Protestant 8%Roman Catholic 3%Hindu 2%

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 Demak (-6.8909°, 110.6396°, elevation 9 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).