Nunukan weather in September

In September, Nunukan sees average daytime highs of 30°C and overnight lows near 24°C, with 186 mm of rain across 27 wet days and about 12 hours of daylight. It is the 4th-warmest and 8th-wettest month of the year here.

Day-to-day highs hold fairly steady near 30°C through the month. The sky is clear or mostly clear about 6% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 06 min at the start of September to 12 hours by month's end. Set against the rest of the year, September is Nunukan's 5th-clearest and 5th-windiest month. For the whole year in context, see Nunukan's year-round climate.

Daytime high
30°
4th warmest
Overnight low
24°
8th coldest
Rainfall
186 mm
27 wet days
Daylight
12 hours
6:03 AM – 6:04 PM
Cloud cover
78%
5th clearest
Wind
5 km/h
5th windiest
Solar energy
5.21 kWh/m²
Travel score
2.8
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 30°C through the month.

A typical September day in Nunukan reaches about 30°C in the afternoon and slips back to 24°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 29°C and 32°C. Set against its neighbours, September runs on par with August and on par with October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13024
23024
33024
43024
53024
63024
73024
83024
93024
103024
113024
123024
133024
143024
153024
163024
173024
183024
193024
203024
213024
223024
233024
243024
253024
263024
273024
283024
293024
303024

How September really feels in Nunukan

Once humidity and wind are folded in, September averages 30 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
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

Nunukan weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 24°16822.411.83.4
Feb30° / 24°12517.611.93.6
Mar31° / 24°15623.4123.2
Apr31° / 25°17226.512.12.8
May31° / 25°22229.912.22.5
Jun30° / 25°21728.212.22.7
Jul30° / 24°19828.612.22.8
Aug30° / 24°19228.512.12.8
Sep30° / 24°18627122.8
Oct30° / 24°22428.611.92.7
Nov30° / 24°1992811.82.6
Dec30° / 24°19726.711.82.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 6% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 79%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12278
22377
32377
42377
52377
62278
72278
82179
92080
102080
112080
121981
131981
141981
151981
161981
171981
181981
192080
201981
211981
221981
232080
242080
252080
262080
272080
281981
291882
301981

Chance of precipitation in September

Any precipitation

Nunukan gets around 186 mm of rain over 27 wet days in September. 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 93% on the wettest days.

0%20%40%60%80%100%151015202530
Rain chance (%)
193
293
392
492
592
691
791
891
990
1090
1190
1289
1389
1489
1589
1689
1789
1889
1989
2089
2189
2290
2390
2490
2590
2691
2791
2891
2991
3091

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the miserable band about 80% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
12377
22377
32377
42377
52377
62377
72278
82278
92278
102278
112278
122179
132179
142179
152080
162080
172080
181981
191981
201882
211882
221783
231783
241783
251684
261684
271684
281684
291585
301585

Wind in September

Winds average 5 km/h in September.

Across September, 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.

0246810151015202530
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
274calm
284calm
294calm
304calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 06 min at the start of September to 12 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over September. Sunrise moves from 6:07 AM to 6:00 AM, and sunset from 6:11 PM to 5:58 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:076:11
212.16:066:11
312.16:066:11
412.16:066:10
512.16:066:10
612.16:066:09
712.16:056:09
812.16:056:08
912.06:056:08
1012.06:056:07
1112.06:046:07
1212.06:046:06
1312.06:046:06
1412.06:046:05
1512.06:036:05
1612.06:036:04
1712.06:036:04
1812.06:036:03
1912.06:026:03
2012.06:026:02
2112.06:026:02
2212.06:026:01
2312.06:016:01
2412.06:016:01
2512.06:016:00
2612.06:016:00
2712.06:005:59
2812.06:005:59
2912.06:005:58
3012.06:005:58

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.21 kWh/m².

For context, solar energy here swings from a low near 4.44 kWh/m² to a high of 5.35 kWh/m² in March across the year — September's 5.21 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.2Bright
75.2Bright
85.2Bright
95.2Bright
105.2Bright
115.2Bright
125.2Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.2Bright
185.2Bright
195.2Bright
205.2Bright
215.2Bright
225.2Bright
235.2Bright
245.2Bright
255.2Bright
265.2Bright
275.2Bright
285.2Bright
295.1Bright
305.1Bright
Planning a trip in September

Hazard calendar for Nunukan

In seasonPeak

In September, Nunukan sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Nunukan sits in the Pacific typhoon belt; the season peaks July–October.

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

Is September a good time to visit Nunukan?

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

2.8
Sightseeing
5th-best month of the year
3.9
Beach & pool
6th-best month of the year

September is a weaker month for outdoor sightseeing in Nunukan.

What to pack for Nunukan in September

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

In September, Nunukan sees daytime highs around 30°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 27 days see rain.

light clothesrain gearsun protection

Sea temperature near Nunukan in September

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

The sea at the nearest coast (about 38 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
Jun30Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov30Tropical
Dec29Tropical

UV index in Nunukan in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Nunukan peaks around March 17 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 11 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 17UV 15Dec 15UV 11
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar15Extreme
Apr14Extreme
May14Extreme
Jun12Extreme
Jul11Extreme
Aug13Extreme
Sep13Extreme
Oct13Extreme
Nov12Extreme
Dec11Extreme

Air quality in Nunukan in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Nunukan is worst in September — around 16 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (January, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodSep 1716 µg/m³Jan 129 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar12Moderate
Apr12Moderate
May12Good
Jun11Good
Jul12Good
Aug14Moderate
Sep16Moderate
Oct15Moderate
Nov11Good
Dec10Good
Location & terrain

Where is Nunukan?

Nunukan sits at 4.1°N, 117.7°E, 19 m above sea level, in Indonesia. The nearest listed city is Tawau, 29 km away.

Topography around Nunukan

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

Within 3 km, the terrain around Nunukan has only modest variations in elevation — a maximum elevation change of 110 m around an average of 18 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 432 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,504 m.

The land around Nunukan is covered by water (45%) and trees (37%) within 3 km, trees (43%), water (30%) and mangroves (22%) within 16 km, and trees (58%) and water (31%) within 80 km.

3 km
110 m
16 km
432 m
80 km
1,504 m
treesgrasslandartificial surfacesbare terrainwatermangroves
September weather nearby: Tawau 29 km · Tarakan 92 km · Semporna 113 km · Lahad Datu 124 km · Malinau 129 km · Tanjung Selor 148 km · Bandar Nabawan 169 km · Sandakan 196 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 Nunukan (4.1384°, 117.6507°, elevation 19 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).