Loa Janan weather in September

In September, Loa Janan sees average daytime highs of 32°C and overnight lows near 23°C, with 167 mm of rain across 20.8 wet days and about 12 hours of daylight. It is the 1st-warmest and 11th-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 7% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 hours at the start of September to 12 hours by month's end. Set against the rest of the year, September is Loa Janan's 2nd-clearest and 2nd-windiest month. For the whole year in context, see Loa Janan's year-round climate.

Daytime high
32°
1st warmest
Overnight low
23°
3rd coldest
Rainfall
167 mm
20.8 wet days
Daylight
12 hours
6:06 AM – 6:06 PM
Cloud cover
76%
2nd clearest
Wind
6 km/h
2nd windiest
Solar energy
5.34 kWh/m²
Travel score
3.0
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

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

A typical September day in Loa Janan reaches about 32°C in the afternoon and slips back to 23°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 33°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)
13123
23123
33123
43123
53123
63123
73123
83123
93123
103223
113223
123223
133223
143223
153223
163223
173223
183223
193223
203223
213223
223223
233223
243223
253223
263223
273223
283223
293223
303223

How September really feels in Loa Janan

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.

Loa Janan weather by month

How September compares with the rest of the year at a glance. September is the 1st-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°27526.3122.6
Feb31° / 24°24223.5122.7
Mar31° / 24°29926.9122.5
Apr31° / 24°30727.5122.4
May31° / 24°25628.7122.4
Jun31° / 24°21425.7122.8
Jul31° / 23°17823.7123.1
Aug31° / 23°15921.2123.2
Sep32° / 23°16720.8123.0
Oct32° / 24°23326122.5
Nov31° / 24°29428.5122.3
Dec31° / 24°29828.9122.4

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 7% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 77%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12872
22773
32773
42773
52773
62674
72575
82575
92476
102476
112476
122377
132377
142377
152377
162377
172377
182377
192377
202377
212278
222278
232278
242278
252278
262179
272179
282080
291882
301882

Chance of precipitation in September

Any precipitation

Loa Janan gets around 167 mm of rain over 20.8 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 70% and peaks near 75% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
172
271
371
471
570
670
769
869
968
1068
1168
1267
1367
1467
1567
1667
1768
1868
1968
2069
2169
2270
2371
2471
2572
2673
2773
2874
2975
3075

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 56% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)Miserable (%)
106238
206238
306337
406337
516237
616237
716237
816237
916237
1016237
1116138
1226038
1325939
1425840
1525741
1625642
1725543
1825444
1925345
2015346
2115247
2215148
2315049
2414950
2514851
2614752
2704753
2804654
2904555
3004555

Wind in September

Winds average 6 km/h in September.

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

0246810151015202530
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
246calm
256calm
266calm
276calm
286calm
296calm
306calm

Sunrise & sunset in September

DaylightNight

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

Days grow by about 0 minutes over September. Sunrise moves from 6:12 AM to 6:01 AM, and sunset from 6:11 PM to 6:01 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.06:126:11
212.06:116:11
312.06:116:10
412.06:116:10
512.06:106:10
612.06:106:09
712.06:096:09
812.06:096:09
912.06:096:08
1012.06:086:08
1112.06:086:08
1212.06:086:07
1312.06:076:07
1412.06:076:07
1512.06:066:06
1612.06:066:06
1712.06:066:05
1812.06:056:05
1912.06:056:05
2012.06:046:04
2112.06:046:04
2212.06:046:04
2312.06:036:03
2412.06:036:03
2512.06:036:03
2612.06:026:02
2712.06:026:02
2812.06:016:02
2912.06:016:01
3012.06:016:01

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.34 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 4.42 kWh/m² to a high of 5.34 kWh/m² in September across the year — September's 5.34 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
65.3Bright
75.3Bright
85.3Bright
95.3Bright
105.3Bright
115.3Bright
125.3Bright
135.3Bright
145.3Bright
155.4Bright
165.4Bright
175.4Bright
185.4Bright
195.4Bright
205.4Bright
215.4Bright
225.4Bright
235.4Bright
245.4Bright
255.4Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
Planning a trip in September

Is September a good time to visit Loa Janan?

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

3.0
Sightseeing
3rd-best month of the year
4.6
Beach & pool
2nd-best month of the year

September is a weaker month for outdoor sightseeing in Loa Janan.

What to pack for Loa Janan in September

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

In September, Loa Janan sees daytime highs around 32°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 21 days see rain.

light clothesrain gearsun protection

Sea temperature near Loa Janan 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 45 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°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May30Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Loa Janan 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 Loa Janan peaks around March 12 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 10 at about 11 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 12UV 15Jul 10UV 11
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar16Extreme
Apr14Extreme
May12Extreme
Jun11Extreme
Jul11Extreme
Aug12Extreme
Sep13Extreme
Oct13Extreme
Nov13Extreme
Dec12Extreme

Air quality in Loa Janan 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 Loa Janan is worst in October — around 28 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (March, 14 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateOct 1427 µg/m³Mar 1314 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb14Moderate
Mar14Moderate
Apr15Moderate
May14Moderate
Jun15Moderate
Jul15Moderate
Aug16Moderate
Sep23Moderate
Oct28Moderate
Nov17Moderate
Dec15Moderate
Location & terrain

Where is Loa Janan?

Loa Janan sits at 0.6°S, 117.1°E, 9 m above sea level, in Indonesia. The nearest listed city is Samarinda, 12 km away.

AmuntaiBarabaiPalu

Topography around Loa Janan

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

Within 3 km, the terrain around Loa Janan has only modest variations in elevation — a maximum elevation change of 131 m around an average of 25 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 264 m; within 80 km, large variations in elevation — a maximum elevation change of 806 m.

The land around Loa Janan is covered by trees (60%) within 3 km, trees (66%) within 16 km, and trees (58%) and water (30%) within 80 km.

3 km
131 m
16 km
264 m
80 km
806 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
September weather nearby: Samarinda 12 km · Balikpapan 82 km · Bontang 91 km · Muara Teweh 248 km · Tanjung 258 km · Amuntai 289 km · Barabai 293 km · Palu 311 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 Loa Janan (-0.5829°, 117.095°, elevation 9 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. 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).