Subulussalam weather in September

In September, Subulussalam sees average daytime highs of 29°C and overnight lows near 21°C, with 295 mm of rain across 22.5 wet days and about 12 hours of daylight. It is the 9th-warmest and 7th-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 September, and the air most often feels oppressive.

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 Subulussalam's 9th-clearest and 4th-windiest month. For the whole year in context, see Subulussalam's year-round climate.

Daytime high
29°
9th warmest
Overnight low
21°
5th coldest
Rainfall
295 mm
22.5 wet days
Daylight
12 hours
6:22 AM – 6:23 PM
Cloud cover
91%
9th clearest
Wind
4 km/h
4th windiest
Solar energy
4.72 kWh/m²
Travel score
3.6
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

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

A typical September day in Subulussalam reaches about 29°C in the afternoon and slips back to 21°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 31°C. Set against its neighbours, September runs on par with August and on par with October.

15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12921
22921
32921
42921
52921
62921
72921
82921
92921
102921
112921
122921
132921
142921
152921
162921
172921
182921
192921
202921
212921
222921
232921
242921
252921
262921
272921
282921
292921
302921

How September really feels in Subulussalam

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

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Subulussalam weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 20°32726.311.93.1
Feb30° / 20°28923.911.92.9
Mar30° / 21°33928.2122.8
Apr30° / 21°36827.312.12.8
May30° / 21°26421.412.13.4
Jun30° / 21°15016.712.23.9
Jul30° / 20°16017.712.14.0
Aug29° / 20°23820.712.13.8
Sep29° / 21°29522.5123.6
Oct29° / 21°4192611.93.4
Nov28° / 21°51028.211.93.1
Dec29° / 21°39527.511.83.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 1% of the time in September.

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

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1496
2496
3496
4496
5496
6496
7496
8496
9496
10496
11496
12496
13496
14496
15496
16496
17496
18496
19397
20298
21298
22298
23298
24298
25298
26298
27298
28298
29298
30298

Chance of precipitation in September

Any precipitation

Subulussalam gets around 295 mm of rain over 22.5 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 75% and peaks near 79% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
173
273
373
473
573
673
773
873
973
1073
1173
1273
1373
1473
1573
1673
1774
1874
1975
2075
2176
2276
2377
2477
2578
2678
2779
2879
2979
3079

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 74% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)
12971
22971
32971
42971
52971
62971
72971
82971
92872
102872
112872
122872
132773
142773
152674
162674
172575
182575
192476
202476
212476
222377
232377
242278
252278
262278
272278
282278
292278
302278

Wind in September

Winds average 4 km/h in September.

Across September, daily wind ranges from about 4 km/h on the calmest days to 4 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
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
224calm
234calm
244calm
254calm
264calm
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 6:27 AM to 6:18 AM, and sunset from 6:30 PM to 6:17 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:276:30
212.06:266:29
312.06:266:29
412.06:266:28
512.06:266:28
612.06:256:28
712.06:256:27
812.06:256:27
912.06:246:26
1012.06:246:26
1112.06:246:25
1212.06:246:25
1312.06:236:25
1412.06:236:24
1512.06:236:24
1612.06:226:23
1712.06:226:23
1812.06:226:22
1912.06:216:22
2012.06:216:21
2112.06:216:21
2212.06:216:21
2312.06:206:20
2412.06:206:20
2512.06:206:19
2612.06:196:19
2712.06:196:18
2812.06:196:18
2912.06:196:18
3012.06:186:17

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.72 kWh/m².

For context, solar energy here swings from a low near 3.85 kWh/m² to a high of 5.26 kWh/m² in February across the year — September's 4.72 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.7Bright
44.7Bright
54.8Bright
64.8Bright
74.8Bright
84.8Bright
94.8Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
144.8Bright
154.8Bright
164.8Bright
174.7Bright
184.7Bright
194.7Bright
204.7Bright
214.7Bright
224.7Bright
234.7Bright
244.6Bright
254.6Bright
264.6Bright
274.6Bright
284.6Bright
294.6Bright
304.5Bright
Planning a trip in September

Hazard calendar for Subulussalam

In seasonPeak

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

Subulussalam sits in the North Indian Ocean cyclone zone; the season peaks May and October–November.

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

Is September a good time to visit Subulussalam?

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

3.6
Sightseeing
4th-best month of the year
4.6
Beach & pool
5th-best month of the year

September is a weaker month for outdoor sightseeing in Subulussalam.

What to pack for Subulussalam in September

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

In September, Subulussalam sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 23 days see rain.

light clothesrain gearsun protection

Sea temperature near Subulussalam in September

The nearest coast averages about 30°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 29 km away) is warmest in May at about 30°C and coldest in November 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
Feb30Tropical
Mar30Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Subulussalam in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 14 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Subulussalam peaks around March 15 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 13 at about 11 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 15UV 14Jul 13UV 11
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar15Extreme
Apr13Extreme
May12Extreme
Jun11Extreme
Jul11Extreme
Aug12Extreme
Sep14Extreme
Oct13Extreme
Nov11Extreme
Dec12Extreme

Air quality in Subulussalam 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 Subulussalam is worst in March — around 25 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMar 1425 µg/m³Dec 1218 µg/m³
PM2.5 (µg/m³)Level
Jan21Moderate
Feb24Moderate
Mar25Moderate
Apr23Moderate
May21Moderate
Jun21Moderate
Jul20Moderate
Aug20Moderate
Sep24Moderate
Oct23Moderate
Nov19Moderate
Dec18Moderate
Location & terrain

Where is Subulussalam?

Subulussalam sits at 2.7°N, 97.9°E, 29 m above sea level, in Indonesia. The nearest listed city is Singkil, 43 km away.

Topography around Subulussalam

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

Within 3 km, the terrain around Subulussalam has only modest variations in elevation — a maximum elevation change of 40 m around an average of 21 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 205 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,429 m.

The land around Subulussalam is covered by trees (90%) within 3 km, trees (92%) within 16 km, and trees (63%) and water (33%) within 80 km.

3 km
40 m
16 km
205 m
80 km
2,429 m
treesshrubsgrasslandcroplandartificial surfaceswater
September weather nearby: Singkil 43 km · Sidikalang 49 km · Paropo 74 km · Tongging 76 km · Kabanjahe 83 km · Pangururan 91 km · Berastagi 91 km · Barus 92 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 Subulussalam (2.662°, 97.8827°, elevation 29 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).