Kertosono weather in December

In December, Kertosono sees average daytime highs of 32°C and overnight lows near 24°C, with 321 mm of rain across 26.2 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 3rd-wettest month of the year here.

Day-to-day highs hold fairly steady near 32°C through the month. The sky is clear or mostly clear about 2% 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 Kertosono's 10th-clearest and 9th-windiest month. For the whole year in context, see Kertosono's year-round climate.

Daytime high
32°
4th warmest
Overnight low
24°
11th coldest
Rainfall
321 mm
26.2 wet days
Daylight
12 h 24 min
5:15 AM – 5:41 PM
Cloud cover
88%
10th clearest
Wind
4 km/h
9th windiest
Solar energy
4.74 kWh/m²
Travel score
2.5
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 32°C through the month.

A typical December day in Kertosono reaches about 32°C in the afternoon and slips back to 24°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 30°C and 34°C. Set against its neighbours, December runs about 1°C cooler than November and on par with January.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13224
23224
33224
43224
53224
63224
73224
83224
93224
103224
113224
123224
133224
143224
153224
163224
173224
183224
193224
203224
213224
223224
233224
243224
253124
263124
273124
283124
293124
303124
313124

How December really feels in Kertosono

Once humidity and wind are folded in, December averages 31 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
31
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.

Kertosono weather by month

How December compares with the rest of the year at a glance. December is the 4th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 24°3792912.42.4
Feb31° / 24°36827.312.22.3
Mar31° / 24°31828.212.12.4
Apr31° / 24°18122.711.82.9
May31° / 23°7812.511.74.1
Jun31° / 23°356.811.64.7
Jul31° / 22°153.311.65.1
Aug32° / 22°51.211.85.0
Sep33° / 22°142.1124.3
Oct33° / 23°618.712.23.4
Nov33° / 24°1681912.32.6
Dec32° / 24°32126.212.42.5

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 2% 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 93%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
11288
21189
31189
41090
51090
61090
7991
8991
9892
10892
11892
12793
13694
14694
15694
16694
17595
18595
19595
20595
21694
22694
23694
24694
25694
26793
27793
28793
29793
30892
31892

Chance of precipitation in December

Any precipitation

Kertosono gets around 321 mm of rain over 26.2 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 85% and peaks near 88% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
179
280
380
481
582
682
783
884
984
1085
1185
1285
1385
1485
1586
1686
1786
1886
1985
2085
2185
2285
2385
2485
2586
2686
2786
2887
2987
3088
3188

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 68% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
137225
227226
327226
427127
517128
617029
717029
816930
906931
1006931
1106832
1206832
1306832
1406733
1506733
1606733
1706733
1806733
1906733
2006733
2106733
2206733
2306733
2406733
2506733
2606733
2706733
2806733
2906733
3006733
3106733

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 5 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
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

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 5:09 AM to 5:22 AM, and sunset from 5:34 PM to 5:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:095:34
212.45:095:34
312.45:105:35
412.45:105:35
512.45:105:36
612.45:115:36
712.45:115:37
812.45:115:37
912.45:125:37
1012.45:125:38
1112.45:135:38
1212.45:135:39
1312.45:135:39
1412.45:145:40
1512.45:145:40
1612.45:155:41
1712.45:155:41
1812.45:155:42
1912.45:165:42
2012.45:165:43
2112.45:175:43
2212.45:175:44
2312.45:185:44
2412.45:185:45
2512.45:195:45
2612.45:195:46
2712.45:205:46
2812.45:205:47
2912.45:215:47
3012.45:215:47
3112.45:225:48

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.74 kWh/m².

For context, solar energy here swings from a low near 4.63 kWh/m² to a high of 6.29 kWh/m² in September across the year — December's 4.74 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.8Bright
44.8Bright
54.8Bright
64.8Bright
74.8Bright
84.8Bright
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
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.8Bright
314.8Bright
Planning a trip in December

Hazard calendar for Kertosono

In seasonPeak

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

Kertosono's monsoon runs December–April, when most of the year's rain falls.

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

Is December a good time to visit Kertosono?

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

2.5
Sightseeing
9th-best month of the year
3.9
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Kertosono.

What to pack for Kertosono in December

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

In December, Kertosono sees daytime highs around 32°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 26 days see rain.

light clothesrain gearsun protection

UV index in Kertosono 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 Kertosono peaks around March 18 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 14 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 highExtremeExtremeMar 18UV 13Jun 14UV 7
UV index (midday)Level
Jan13Extreme
Feb11Extreme
Mar13Extreme
Apr11Extreme
May9Very high
Jun7High
Jul9Very high
Aug11Extreme
Sep13Extreme
Oct12Extreme
Nov10Very high
Dec12Extreme

Air quality in Kertosono 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 Kertosono is worst in May — around 64 µg/m³ PM2.5 (unhealthy), and holds fairly steady the rest of the year.

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecPoorUnhealthyPoorMay 1764 µg/m³Dec 2343 µg/m³
PM2.5 (µg/m³)Level
Jan44Poor
Feb45Poor
Mar53Poor
Apr59Unhealthy
May64Unhealthy
Jun60Unhealthy
Jul54Poor
Aug48Poor
Sep47Poor
Oct49Poor
Nov48Poor
Dec43Poor
Location & terrain

Where is Kertosono?

Kertosono sits at 7.6°S, 112.1°E, 43 m above sea level, in Indonesia. The nearest listed city is Diwek, 14 km away.

Topography around Kertosono

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

Within 3 km, the terrain around Kertosono has only modest variations in elevation — a maximum elevation change of 13 m around an average of 42 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 248 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,305 m.

The land around Kertosono is covered by cropland (52%), trees (23%) and artificial surfaces (22%) within 3 km, cropland (55%) and trees (28%) within 16 km, and trees (49%) and cropland (37%) within 80 km.

3 km
13 m
16 km
248 m
80 km
3,305 m
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Diwek 14 km · Jombang 15 km · Ngoro 21 km · Gampengrejo 21 km · Nganjuk 22 km · Pare 23 km · Kediri 28 km · Mojoagung 28 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 Kertosono (-7.5833°, 112.1°, elevation 43 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. 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).