Slawi weather in January

In January, Slawi sees average daytime highs of 29°C and overnight lows near 24°C, with 472 mm of rain across 30.4 wet days and about 12.4 hours of daylight. It is the 10th-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 0% of the time in January, and the air most often feels oppressive.

Daylight stretches from about 12 h 24 min at the start of January to 12 h 18 min by month's end. Set against the rest of the year, January is Slawi's 10th-clearest and 3rd-windiest month. For the whole year in context, see Slawi's year-round climate.

Daytime high
29°
10th warmest
Overnight low
24°
7th coldest
Rainfall
472 mm
30.4 wet days
Daylight
12 h 24 min
5:42 AM – 6:04 PM
Cloud cover
92%
10th clearest
Wind
5 km/h
3rd windiest
Solar energy
4.73 kWh/m²
Travel score
2.9
out of 10

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

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

A typical January day in Slawi reaches about 29°C in the afternoon and slips back to 24°C overnight — a 5°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, January runs on par with December and on par with February.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12924
22924
32924
42924
52924
62924
72924
82924
92924
102924
112924
122924
132924
142924
152924
162924
172924
182924
192924
202924
212924
222924
232824
242824
252824
262824
272824
282824
292824
302824
312824

How January really feels in Slawi

Once humidity and wind are folded in, January averages 12 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
12
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

Slawi weather by month

How January compares with the rest of the year at a glance. January is the 10th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 24°47230.412.42.9
Feb29° / 24°44327.712.22.8
Mar29° / 24°41530.5122.8
Apr30° / 24°31228.111.92.9
May30° / 24°16622.111.73.7
Jun29° / 24°9915.111.64.7
Jul29° / 23°6410.811.65.6
Aug29° / 22°397.511.85.9
Sep29° / 23°6310125.2
Oct30° / 24°17119.812.23.9
Nov29° / 24°35027.412.33.0
Dec29° / 24°45929.912.42.8

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 0% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 3% of January, with mostly cloudy or overcast conditions the remaining 97%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
1496
2496
3496
4496
5496
6595
7595
8595
9595
10595
11595
12595
13595
14595
15496
16496
17496
18496
19397
20397
21397
22397
23298
24298
25298
26298
27298
28199
29199
30199
31199

Chance of precipitation in January

Any precipitation

Slawi gets around 472 mm of rain over 30.4 wet days in January, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 98% and peaks near 100% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
197
296
396
496
596
696
796
897
997
1097
1197
1297
1397
1498
1598
1698
1799
1899
1999
2099
2199
2299
23100
24100
25100
26100
27100
28100
29100
30100
31100

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January lands in the oppressive band about 94% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Oppressive (%)Miserable (%)
1964
2964
3964
4964
5964
6964
7964
8964
9964
10964
11955
12955
13955
14955
15946
16946
17946
18937
19937
20937
21937
22937
23937
24937
25937
26937
27937
28937
29937
30946
31946

Wind in January

Winds average 5 km/h in January.

Across January, 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
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 12 h 24 min at the start of January to 12 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over January. Sunrise moves from 5:35 AM to 5:48 AM, and sunset from 5:59 PM to 6:06 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:355:59
212.45:355:59
312.45:365:59
412.45:366:00
512.45:376:00
612.45:376:01
712.45:386:01
812.45:386:01
912.45:396:02
1012.45:396:02
1112.45:396:02
1212.45:406:03
1312.45:406:03
1412.45:416:03
1512.45:416:03
1612.45:426:04
1712.45:426:04
1812.45:436:04
1912.45:436:04
2012.45:446:05
2112.35:446:05
2212.35:446:05
2312.35:456:05
2412.35:456:05
2512.35:456:05
2612.35:466:06
2712.35:466:06
2812.35:476:06
2912.35:476:06
3012.35:476:06
3112.35:486:06

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 4.73 kWh/m².

For context, solar energy here swings from a low near 4.67 kWh/m² to a high of 5.95 kWh/m² in September across the year — January's 4.73 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.7Bright
44.8Bright
54.8Bright
64.8Bright
74.8Bright
84.8Bright
94.8Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
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
274.6Bright
284.6Bright
294.6Bright
304.6Bright
314.6Bright
Planning a trip in January

Hazard calendar for Slawi

In seasonPeak

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

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

Slawi'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 January a good time to visit Slawi?

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

2.9
Sightseeing
8th-best month of the year
3.6
Beach & pool
11th-best month of the year

January is a weaker month for outdoor sightseeing in Slawi.

What to pack for Slawi in January

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

In January, Slawi sees daytime highs around 29°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 30 days see rain.

light clothesrain gearsun protection

Sea temperature near Slawi in January

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

The sea offshore 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
Jun30Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov30Tropical
Dec30Tropical

UV index in Slawi in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January 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 Slawi peaks around March 15 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 16 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 15UV 14Nov 16UV 6
UV index (midday)Level
Jan12Extreme
Feb12Extreme
Mar14Extreme
Apr11Extreme
May8Very high
Jun8Very high
Jul9Very high
Aug11Extreme
Sep12Extreme
Oct11Extreme
Nov6High
Dec12Extreme

Air quality in Slawi in January

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Slawi is worst in May — around 42 µg/m³ PM2.5 (poor), and holds fairly steady the rest of the year.

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModeratePoorModerateMay 1641 µg/m³Feb 1231 µg/m³
PM2.5 (µg/m³)Level
Jan33Moderate
Feb31Moderate
Mar37Poor
Apr38Poor
May42Poor
Jun38Poor
Jul35Moderate
Aug35Moderate
Sep36Poor
Oct37Poor
Nov34Moderate
Dec33Moderate
Location & terrain

Where is Slawi?

Slawi sits at 7.0°S, 109.1°E, 43 m above sea level, in Indonesia. The nearest listed city is Adiwerna, 5.0 km away.

Topography around Slawi

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

Within 3 km, the terrain around Slawi has only modest variations in elevation — a maximum elevation change of 45 m around an average of 40 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 764 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,396 m.

The land around Slawi is covered by artificial surfaces (37%), trees (36%) and cropland (21%) within 3 km, cropland (37%) and trees (35%) within 16 km, and trees (47%) and water (29%) within 80 km.

3 km
45 m
16 km
764 m
80 km
3,396 m
treesgrasslandcroplandartificial surfaceswaterwetland
January weather nearby: Adiwerna 5.0 km · Tarub 6.0 km · Lebaksiu 8.0 km · Balapulang 9.0 km · Dukuhturi 11 km · Tegal 12 km · Margasari 18 km · Bulakamba 24 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 Slawi (-6.9816°, 109.1407°, 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. 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).