Boyolali weather in December

In December, Boyolali sees average daytime highs of 28°C and overnight lows near 21°C, with 387 mm of rain across 27.9 wet days and about 12.4 hours of daylight. It is the 8th-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 1% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 12 h 24 min at the start of December to 12 h 24 min by month's end. Set against the rest of the year, December is Boyolali's 11th-clearest and 7th-windiest month. For the whole year in context, see Boyolali's year-round climate.

Daytime high
28°
8th warmest
Overnight low
21°
11th coldest
Rainfall
387 mm
27.9 wet days
Daylight
12 h 24 min
5:21 AM – 5:47 PM
Cloud cover
92%
11th clearest
Wind
4 km/h
7th windiest
Solar energy
4.52 kWh/m²
Travel score
3.3
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical December day in Boyolali reaches about 28°C in the afternoon and slips back to 21°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 30°C. Set against its neighbours, December runs on par with November and on par with January.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12821
22821
32821
42821
52821
62821
72821
82821
92821
102821
112821
122821
132821
142821
152821
162821
172821
182821
192821
202821
212821
222821
232821
242821
252821
262821
272821
282821
292821
302821
312821

Boyolali weather by month

How December compares with the rest of the year at a glance. December is the 8th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 21°44729.212.43.2
Feb28° / 21°45127.412.23.0
Mar29° / 21°40729.312.13.0
Apr29° / 21°28226.711.83.3
May29° / 21°14820.411.74.3
Jun28° / 20°9614.711.65.3
Jul28° / 19°6210.411.66.3
Aug28° / 19°426.811.86.8
Sep28° / 20°719.6125.7
Oct29° / 21°17919.712.24.3
Nov29° / 21°34026.912.33.3
Dec28° / 21°38727.912.43.3

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 1% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 3% of December, with mostly cloudy or overcast conditions the remaining 96%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
1496
2496
3397
4397
5496
6496
7496
8496
9397
10397
11397
12397
13397
14397
15397
16397
17397
18397
19496
20496
21496
22496
23496
24496
25496
26595
27595
28595
29595
30595
31595

Chance of precipitation in December

Any precipitation

Boyolali gets around 387 mm of rain over 27.9 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 90% and peaks near 92% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
192
292
392
492
592
692
792
892
992
1092
1192
1291
1391
1491
1591
1690
1790
1889
1989
2089
2188
2288
2388
2488
2588
2688
2788
2889
2989
3089
3190

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the oppressive band about 71% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)
12377
22377
32377
42377
52377
62377
72377
82377
92377
102377
112476
122476
132575
142674
152773
162872
172971
183070
193169
203268
213367
223466
233466
243565
253565
263565
273565
283565
293565
303565
313565

Wind in December

Winds average 4 km/h in December.

Across December, daily wind ranges from about 4 km/h on the calmest days to 4 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 12 h 24 min at the start of December to 12 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 0 minutes over December. Sunrise moves from 5:15 AM to 5:28 AM, and sunset from 5:40 PM to 5:54 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:155:40
212.45:155:40
312.45:165:41
412.45:165:41
512.45:165:41
612.45:175:42
712.45:175:42
812.45:175:43
912.45:185:43
1012.45:185:44
1112.45:195:44
1212.45:195:45
1312.45:195:45
1412.45:205:46
1512.45:205:46
1612.45:215:47
1712.45:215:47
1812.45:225:48
1912.45:225:48
2012.45:235:49
2112.45:235:49
2212.45:235:50
2312.45:245:50
2412.45:245:51
2512.45:255:51
2612.45:255:52
2712.45:265:52
2812.45:265:52
2912.45:275:53
3012.45:275:53
3112.45:285:54

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.52 kWh/m².

For context, solar energy here swings from a low near 4.49 kWh/m² to a high of 5.86 kWh/m² in September across the year — December's 4.52 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.6Bright
54.5Bright
64.5Bright
74.5Bright
84.5Bright
94.5Bright
104.5Bright
114.5Bright
124.5Bright
134.5Bright
144.5Bright
154.5Bright
164.5Bright
174.5Bright
184.5Bright
194.5Bright
204.5Bright
214.5Bright
224.5Bright
234.5Bright
244.5Bright
254.6Bright
264.6Bright
274.6Bright
284.6Bright
294.5Bright
304.5Bright
314.5Bright
Planning a trip in December

Hazard calendar for Boyolali

In seasonPeak

In December, Boyolali sits inside its cyclone and rainy season season. The full year is below, with each hazard's peak months called out.

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

Boyolali's rainy season runs November–April, when most of the year's rain falls.

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

Is December a good time to visit Boyolali?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

3.3
Sightseeing
7th-best month of the year
3.8
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Boyolali.

What to pack for Boyolali in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Boyolali sees daytime highs around 28°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 28 days see rain.

light clothesrain gearsun protection

Sea temperature near Boyolali in December

The nearest coast averages about 29°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 64 km away) is warmest in March at about 29°C and coldest in August near 25°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May29Tropical
Jun28Warm
Jul26Warm
Aug25Warm
Sep25Warm
Oct26Warm
Nov28Warm
Dec29Tropical

UV index in Boyolali in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Boyolali peaks around March 14 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 14 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highVery highExtremeExtremeMar 14UV 15Jun 14UV 6
UV index (midday)Level
Jan14Extreme
Feb14Extreme
Mar15Extreme
Apr12Extreme
May8Very high
Jun6High
Jul10Very high
Aug11Extreme
Sep13Extreme
Oct13Extreme
Nov9Very high
Dec11Extreme

Air quality in Boyolali in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Boyolali is worst in April — around 58 µg/m³ PM2.5 (unhealthy), about 1.7× the cleanest month (September, 34 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorUnhealthyPoorModeratePoorApr 2158 µg/m³Sep 1134 µg/m³
PM2.5 (µg/m³)Level
Jan48Poor
Feb46Poor
Mar54Poor
Apr58Unhealthy
May57Unhealthy
Jun51Poor
Jul42Poor
Aug35Moderate
Sep34Moderate
Oct37Poor
Nov42Poor
Dec42Poor
Location & terrain

Where is Boyolali?

Boyolali sits at 7.5°S, 110.6°E, 438 m above sea level, in Indonesia. The nearest listed city is Karanganom, 13 km away.

Topography around Boyolali

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

Within 3 km, the terrain around Boyolali has significant variations in elevation — a maximum elevation change of 260 m around an average of 440 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,558 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,291 m.

The land around Boyolali is covered by trees (64%) and artificial surfaces (31%) within 3 km, trees (67%) within 16 km, and trees (61%) and cropland (21%) within 80 km.

3 km
260 m
16 km
2,558 m
80 km
3,291 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Karanganom 13 km · Delanggu 13 km · Ngemplak 13 km · Gatak 14 km · Kartasura 16 km · Colomadu 17 km · Ceper 18 km · Kebonarun 19 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 Boyolali (-7.5331°, 110.5958°, elevation 438 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).