Waisai weather in September

In September, Waisai sees average daytime highs of 28°C and overnight lows near 25°C, with 185 mm of rain across 21.2 wet days and about 12 hours of daylight. It is the 9th-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 10% 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 Waisai's 2nd-clearest and 3rd-windiest month. For the whole year in context, see Waisai's year-round climate.

Daytime high
28°
9th warmest
Overnight low
25°
3rd coldest
Rainfall
185 mm
21.2 wet days
Daylight
12 hours
6:12 AM – 6:12 PM
Cloud cover
74%
2nd clearest
Wind
10 km/h
3rd windiest
Solar energy
5.71 kWh/m²
Travel score
4.5
out of 10

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 Waisai reaches about 28°C in the afternoon and slips back to 25°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 29°C. Set against its neighbours, September runs on par with August and on par with October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12825
22825
32825
42825
52825
62825
72825
82825
92825
102825
112825
122825
132825
142825
152825
162825
172825
182825
192825
202825
212825
222825
232825
242825
252825
262825
272825
282825
292825
302825

How September really feels in Waisai

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.

Waisai weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 25°24626.6123.6
Feb28° / 25°19323.3123.7
Mar28° / 25°25826.4123.5
Apr28° / 25°28627.6123.3
May28° / 26°27427.1123.5
Jun28° / 25°27925124.0
Jul27° / 25°23123.4124.3
Aug27° / 25°16919.2124.9
Sep28° / 25°18521.2124.5
Oct28° / 25°20022.8124.1
Nov28° / 25°22026.1123.5
Dec28° / 25°26628.6123.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 10% 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 72%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12773
22674
32674
42575
52476
62476
72476
82476
92476
102476
112476
122575
132674
142674
152773
162872
172971
182971
193070
203070
213070
223169
233169
243268
253268
263268
273070
283070
293070
302971

Chance of precipitation in September

Any precipitation

Waisai gets around 185 mm of rain over 21.2 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 71% and peaks near 72% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
168
269
370
471
571
671
771
872
972
1072
1172
1271
1371
1471
1570
1670
1770
1870
1970
2070
2170
2270
2370
2470
2570
2670
2771
2871
2971
3071

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 90% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)Miserable (%)
10946
21936
31936
41936
51936
61936
71936
82926
92926
102917
112917
122917
132917
142917
152908
162908
172908
181909
191909
201909
2118910
2218910
2318811
2408911
2508812
2608713
2708614
2808614
2908515
3008416

Wind in September

Winds average 10 km/h in September.

Across September, daily wind ranges from about 9 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
611calm
711calm
811calm
911calm
1011calm
1111calm
1211calm
1311calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
279calm
289calm
299calm
309calm

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 6:18 AM to 6:07 AM, and sunset from 6:18 PM to 6:07 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.06:186:18
212.06:176:17
312.06:176:17
412.06:176:17
512.06:166:16
612.06:166:16
712.06:166:16
812.06:156:15
912.06:156:15
1012.06:156:14
1112.06:146:14
1212.06:146:14
1312.06:136:13
1412.06:136:13
1512.06:136:13
1612.06:126:12
1712.06:126:12
1812.06:126:12
1912.06:116:11
2012.06:116:11
2112.06:106:10
2212.06:106:10
2312.06:106:10
2412.06:096:09
2512.06:096:09
2612.06:096:09
2712.06:086:08
2812.06:086:08
2912.06:086:08
3012.06:076:07

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.71 kWh/m².

For context, solar energy here swings from a low near 4.82 kWh/m² to a high of 5.79 kWh/m² in October across the year — September's 5.71 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.6Bright
85.6Bright
95.6Bright
105.6Bright
115.6Bright
125.6Bright
135.7Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.8Bright
195.8Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.8Bright
255.8Bright
265.9Bright
275.9Bright
285.9Bright
295.9Bright
305.9Bright
Planning a trip in September

Is September a good time to visit Waisai?

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

4.5
Sightseeing
2nd-best month of the year
4.8
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Waisai for sightseeing.

What to pack for Waisai in September

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

In September, Waisai sees daytime highs around 28°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 21 days see rain.

light clothesrain gearsun protection

Sea temperature near Waisai 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 19 km away) is warmest in May at about 29°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
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Waisai 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 Waisai peaks around March 17 at about 16 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 at about 12 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 17UV 16Jul 12UV 12
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar16Extreme
Apr15Extreme
May12Extreme
Jun12Extreme
Jul12Extreme
Aug13Extreme
Sep14Extreme
Oct15Extreme
Nov13Extreme
Dec12Extreme
Location & terrain

Where is Waisai?

Waisai sits at 0.2°S, 130.5°E, 185 m above sea level, in Indonesia. The nearest listed city is Sorong, 110 km away.

SofifiTobeloDarubaFakfakTernateKawasi

Topography around Waisai

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

Within 3 km, the terrain around Waisai has significant variations in elevation — a maximum elevation change of 411 m around an average of 151 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 733 m; within 80 km, large variations in elevation — a maximum elevation change of 1,155 m.

The land around Waisai is covered by trees (75%) and water (23%) within 3 km, trees (66%) and water (32%) within 16 km, and water (81%) within 80 km.

3 km
411 m
16 km
733 m
80 km
1,155 m
treeswatermangroves
September weather nearby: Sorong 110 km · Teminabuan 214 km · Sofifi 345 km · Tobelo 353 km · Daruba 354 km · Fakfak 359 km · Ternate 366 km · Kawasi 376 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 Waisai (-0.2379°, 130.5072°, elevation 185 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).