Aileu weather in September

In September, Aileu sees average daytime highs of 28°C and overnight lows near 17°C, with 15 mm of rain across 2.2 wet days and about 11.9 hours of daylight. It is the 3rd-warmest and 11th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 43% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 11 h 48 min at the start of September to 12 h 06 min by month's end. Set against the rest of the year, September is Aileu's 1st-clearest and 7th-windiest month. For the whole year in context, see Aileu's year-round climate.

Daytime high
28°
3rd warmest
Overnight low
17°
3rd coldest
Rainfall
15 mm
2.2 wet days
Daylight
12 hours
6:33 AM – 6:31 PM
Cloud cover
47%
1st clearest
Wind
4 km/h
7th windiest
Solar energy
6.45 kWh/m²
Travel score
7.2
out of 10

Aileu is A town in Timor-Leste.

Density
69/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical September day in Aileu reaches about 28°C in the afternoon and slips back to 17°C overnight — a 11°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, September runs about 1°C warmer than August and on par with October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12817
22817
32817
42817
52817
62817
72817
82817
92817
102817
112817
122817
132817
142817
152817
162817
172817
182817
192817
202817
212817
222817
232817
242918
252918
262918
272918
282918
292918
302918

Aileu weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 20°34529.512.53.5
Feb26° / 20°3262712.33.5
Mar26° / 20°30727.412.13.9
Apr27° / 19°18719.311.84.9
May27° / 19°811211.66.2
Jun26° / 18°416.711.57.1
Jul26° / 17°194.411.57.5
Aug27° / 16°81.511.77.9
Sep28° / 17°152.211.97.2
Oct29° / 19°416.612.26.0
Nov28° / 20°15717.812.44.7
Dec27° / 20°33428.812.53.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 23% of September, with mostly cloudy or overcast conditions the remaining 34%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16733
26832
36832
46832
56832
66832
76832
86832
96832
106832
116733
126733
136733
146733
156733
166733
176733
186634
196634
206535
216535
226436
236436
246337
256337
266238
276238
286139
296139
306139

Chance of precipitation in September

Any precipitation

Aileu gets around 15 mm of rain over 2.2 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 7% and peaks near 10% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
15
25
35
45
55
66
76
86
96
106
116
126
137
147
157
167
177
188
198
208
218
228
239
249
259
269
279
289
2910
3010

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 46% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
12347273
22347273
32447273
42447263
52447263
62447263
72447263
82447253
92447253
102448254
112448254
122447254
132447254
142447254
152347265
162346265
172246265
182146276
192146276
202046277
211946277
221946287
231846288
241846288
251745299
261645299
2716453010
2815453010
2914443110
3014443211

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 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
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 11 h 48 min at the start of September to 12 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over September. Sunrise moves from 6:43 AM to 6:25 AM, and sunset from 6:32 PM to 6:29 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.86:436:32
211.86:426:32
311.86:416:32
411.96:416:32
511.96:406:32
611.96:406:32
711.96:396:32
811.96:386:32
911.96:386:32
1011.96:376:31
1111.96:376:31
1211.96:366:31
1311.96:356:31
1411.96:356:31
1511.96:346:31
1612.06:336:31
1712.06:336:31
1812.06:326:30
1912.06:326:30
2012.06:316:30
2112.06:306:30
2212.06:306:30
2312.06:296:30
2412.06:296:30
2512.06:286:30
2612.06:276:29
2712.06:276:29
2812.16:266:29
2912.16:266:29
3012.16:256:29

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.45 kWh/m².

For context, solar energy here swings from a low near 4.64 kWh/m² to a high of 6.62 kWh/m² in October across the year — September's 6.45 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.2Intense
26.2Intense
36.2Intense
46.3Intense
56.3Intense
66.3Intense
76.3Intense
86.3Intense
96.4Intense
106.4Intense
116.4Intense
126.4Intense
136.4Intense
146.4Intense
156.4Intense
166.4Intense
176.5Intense
186.5Intense
196.5Intense
206.5Intense
216.5Intense
226.5Intense
236.5Intense
246.5Intense
256.5Intense
266.6Intense
276.6Intense
286.6Intense
296.6Intense
306.6Intense
Planning a trip in September

Hazard calendar for Aileu

In seasonPeak

None of Aileu's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

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

Aileu's monsoon runs November–April, when most of the year's rain falls.

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

Is September a good time to visit Aileu?

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

7.2
Sightseeing
3rd-best month of the year
8.2
Beach & pool
1st-best month of the year

September is one of the better times to visit Aileu for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Aileu in September

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

In September, Aileu sees daytime highs around 28°C and nights near 17°C. Pack light clothes and sun protection.

light clothessun protection

Sea temperature near Aileu in September

The nearest coast averages about 28°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 40 km away) is warmest in November at about 30°C and coldest in August near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May29Tropical
Jun28Tropical
Jul28Warm
Aug27Warm
Sep28Warm
Oct29Tropical
Nov30Tropical
Dec30Tropical

UV index in Aileu in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 15 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Aileu peaks around March 10 at about 16 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 10 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 10UV 16Jul 10UV 10
UV index (midday)Level
Jan14Extreme
Feb16Extreme
Mar16Extreme
Apr14Extreme
May11Extreme
Jun10Very high
Jul10Very high
Aug12Extreme
Sep15Extreme
Oct14Extreme
Nov14Extreme
Dec13Extreme
Location & terrain

Where is Aileu?

Aileu sits at 8.7°S, 125.6°E, 913 m above sea level, in Timor Leste. The nearest listed city is Gleno, 14 km away.

AtsabeLiquiçáMaubaraMalianaSuaiAtambua

Topography around Aileu

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

Within 3 km, the terrain around Aileu has significant variations in elevation — a maximum elevation change of 339 m around an average of 994 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,315 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,916 m.

The land around Aileu is covered by grassland (66%) and trees (26%) within 3 km, grassland (51%) and trees (48%) within 16 km, and water (50%) and trees (36%) within 80 km.

3 km
339 m
16 km
2,315 m
80 km
2,916 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Gleno 14 km · Dili 19 km · Atsabe 29 km · Liquiçá 29 km · Maubara 42 km · Maliana 48 km · Suai 73 km · Atambua 85 km

Timor Leste travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / E / F / I
220 V · 50 Hz
Prices
≈ 28% of US
price level, 2025
GDP per capita
$1,341
2025
Homicide rate
4.1
per 100k, 2015
Road deaths
11.9
per 100k/yr, 2019
Income group
Lower middle
World Bank
Religion
Catholic 91%other 7%Protestant Evangelical 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 Aileu (-8.7281°, 125.5664°, elevation 913 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).