Sumber weather in December

In December, Sumber sees average daytime highs of 29°C and overnight lows near 24°C, with 343 mm of rain across 28.9 wet days and about 12.4 hours of daylight. It is the 9th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°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 Sumber's 10th-clearest and 10th-windiest month. For the whole year in context, see Sumber's year-round climate.

Daytime high
29°
9th warmest
Overnight low
24°
8th coldest
Rainfall
343 mm
28.9 wet days
Daylight
12 h 24 min
5:31 AM – 5:54 PM
Cloud cover
89%
10th clearest
Wind
6 km/h
10th windiest
Solar energy
4.68 kWh/m²
Travel score
3.0
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical December day in Sumber reaches about 29°C in the afternoon and slips back to 24°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 30°C. Set against its neighbours, December runs on par with November and on par with January.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12925
22925
32925
42925
52924
62924
72924
82924
92924
102924
112924
122924
132924
142924
152924
162924
172924
182924
192924
202924
212924
222924
232924
242924
252924
262924
272924
282924
292924
302924
312924

How December really feels in Sumber

Once humidity and wind are folded in, December averages 11 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
11
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in December is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Sumber weather by month

How December compares with the rest of the year at a glance. December is the 9th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 24°33729.612.33.1
Feb28° / 24°31627.312.23.0
Mar29° / 24°31129.5123.0
Apr29° / 25°20925.611.93.4
May29° / 25°9617.211.74.5
Jun29° / 24°5610.711.65.4
Jul29° / 24°31611.66.1
Aug29° / 23°133.111.86.4
Sep30° / 24°284.9125.7
Oct30° / 24°8612.512.24.7
Nov29° / 25°22823.112.33.5
Dec29° / 24°34328.912.43.0

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 5% of December, with mostly cloudy or overcast conditions the remaining 94%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
1793
2694
3694
4694
5694
6694
7694
8694
9694
10694
11694
12694
13793
14793
15793
16793
17694
18595
19595
20595
21595
22595
23595
24595
25595
26595
27595
28595
29694
30694
31793

Chance of precipitation in December

Any precipitation

Sumber gets around 343 mm of rain over 28.9 wet days in December, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 93% and peaks near 94% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
191
291
391
492
592
692
792
892
993
1093
1193
1293
1393
1493
1593
1694
1794
1894
1994
2094
2194
2294
2394
2494
2594
2694
2794
2894
2993
3093
3193

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 99% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
11990
21990
31990
41990
51990
61990
71990
81990
901000
1001000
1101000
1201000
1301000
1401000
1501000
1601000
1701000
1801000
1901000
2001000
2101000
2201000
2301000
2401000
2501000
2601000
2701000
2801000
290991
300991
310991

Wind in December

Winds average 6 km/h in December.

Across December, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

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 5:25 AM to 5:38 AM, and sunset from 5:47 PM to 6:01 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:255:47
212.45:255:47
312.45:265:48
412.45:265:48
512.45:265:49
612.45:275:49
712.45:275:50
812.45:275:50
912.45:285:51
1012.45:285:51
1112.45:285:52
1212.45:295:52
1312.45:295:52
1412.45:305:53
1512.45:305:53
1612.45:315:54
1712.45:315:54
1812.45:315:55
1912.45:325:55
2012.45:325:56
2112.45:335:56
2212.45:335:57
2312.45:345:57
2412.45:345:58
2512.45:355:58
2612.45:355:59
2712.45:365:59
2812.45:366:00
2912.45:376:00
3012.45:376:00
3112.45:386:01

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.68 kWh/m².

For context, solar energy here swings from a low near 4.62 kWh/m² to a high of 6.17 kWh/m² in September across the year — December's 4.68 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.8Bright
24.8Bright
34.8Bright
44.8Bright
54.8Bright
64.7Bright
74.7Bright
84.7Bright
94.7Bright
104.7Bright
114.7Bright
124.7Bright
134.7Bright
144.7Bright
154.7Bright
164.7Bright
174.7Bright
184.7Bright
194.7Bright
204.7Bright
214.7Bright
224.7Bright
234.7Bright
244.7Bright
254.7Bright
264.7Bright
274.7Bright
284.7Bright
294.7Bright
304.7Bright
314.7Bright
Planning a trip in December

Hazard calendar for Sumber

In seasonPeak

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

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

Sumber'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

Is December a good time to visit Sumber?

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

3.0
Sightseeing
10th-best month of the year
3.8
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Sumber.

What to pack for Sumber in December

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

In December, Sumber sees daytime highs around 29°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 29 days see rain.

light clothesrain gearsun protection

Sea temperature near Sumber 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 22 km away) is warmest in May at about 30°C and coldest in August near 28°C.

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

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr30Tropical
May30Tropical
Jun29Tropical
Jul29Tropical
Aug28Tropical
Sep29Tropical
Oct29Tropical
Nov30Tropical
Dec29Tropical

UV index in Sumber in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sumber peaks around March 12 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 14 at about 8 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeVery highExtremeMar 12UV 14Jun 14UV 8
UV index (midday)Level
Jan10Extreme
Feb13Extreme
Mar14Extreme
Apr12Extreme
May9Very high
Jun8Very high
Jul9Very high
Aug11Extreme
Sep13Extreme
Oct12Extreme
Nov8Very high
Dec12Extreme

Air quality in Sumber 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 Sumber is worst in May — around 54 µg/m³ PM2.5 (poor), and holds fairly steady the rest of the year.

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorMay 1654 µg/m³Aug 2244 µg/m³
PM2.5 (µg/m³)Level
Jan47Poor
Feb46Poor
Mar52Poor
Apr51Poor
May54Poor
Jun51Poor
Jul46Poor
Aug44Poor
Sep44Poor
Oct45Poor
Nov44Poor
Dec46Poor
Location & terrain

Where is Sumber?

Sumber sits at 6.8°S, 108.5°E, 72 m above sea level, in Indonesia. The nearest listed city is Weru, 6.0 km away.

Topography around Sumber

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

Within 3 km, the terrain around Sumber has significant variations in elevation — a maximum elevation change of 266 m around an average of 88 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,688 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,025 m.

The land around Sumber is covered by trees (49%) and artificial surfaces (29%) within 3 km, trees (41%) and cropland (27%) within 16 km, and trees (39%), water (29%) and cropland (24%) within 80 km.

3 km
266 m
16 km
2,688 m
80 km
3,025 m
treesgrasslandcroplandartificial surfaceswaterwetland
December weather nearby: Weru 6.0 km · Plumbon 6.0 km · Klangenan 7.0 km · Palimanan 9.0 km · Cirebon 10 km · Arjawinangun 15 km · Astanajapura 17 km · Karangsembung 20 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 Sumber (-6.7603°, 108.4831°, elevation 72 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).