Nuku‘alofa weather in September

In September, Nuku‘alofa sees average daytime highs of 23°C and overnight lows near 22°C, with 106 mm of rain across 9.5 wet days and about 11.9 hours of daylight. It is the 11th-warmest and 6th-wettest month of the year here.

Day-to-day highs hold fairly steady near 23°C through the month. The sky is clear or mostly clear about 31% of the time in September, and the air most often feels humid.

Daylight stretches from about 11 h 36 min at the start of September to 12 h 12 min by month's end. Set against the rest of the year, September is Nuku‘alofa's 1st-clearest and 8th-windiest month. For the whole year in context, see Nuku‘alofa's year-round climate.

Daytime high
23°
11th warmest
Overnight low
22°
2nd coldest
Rainfall
106 mm
9.5 wet days
Daylight
11 h 54 min
6:39 AM – 6:32 PM
Cloud cover
59%
1st clearest
Wind
24 km/h
8th windiest
Solar energy
5 kWh/m²
Travel score
6.9
out of 10

Nuku‘alofa is capital city of Tonga.

Density
1,963/km²
people per km²
Founded
1795

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 23°C through the month.

A typical September day in Nuku‘alofa reaches about 23°C in the afternoon and slips back to 22°C overnight — a 1°C spread between the day's warmth and the night's chill. On most days the high lands between 21°C and 24°C. Set against its neighbours, September runs on par with August and on par with October.

15°18°20°23°25°151015202530
Avg high (°C)Avg low (°C)
12321
22321
32321
42321
52321
62322
72322
82322
92322
102322
112322
122322
132322
142322
152322
162322
172322
182322
192322
202322
212322
222322
232322
242322
252322
262322
272322
282322
292322
302322

Nuku‘alofa weather by month

How September compares with the rest of the year at a glance. September is the 11th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 25°19515.513.15.7
Feb27° / 26°20316.512.75.3
Mar27° / 26°23018.312.15.3
Apr26° / 25°16713.411.56.0
May25° / 24°10310.1116.8
Jun24° / 23°1068.810.77.0
Jul23° / 22°968.410.87.0
Aug23° / 21°1098.611.36.9
Sep23° / 22°1069.511.96.9
Oct23° / 22°938.512.57.1
Nov25° / 23°999.2136.9
Dec26° / 25°10512.113.36.4

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 20% of September, with mostly cloudy or overcast conditions the remaining 49%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15050
25050
35050
45050
55050
65050
75050
85050
95149
105149
115149
125149
135149
145149
155149
165149
175149
185149
195050
205050
215050
225050
235050
245149
255149
265149
275149
285149
295149
305149

Chance of precipitation in September

Any precipitation

Nuku‘alofa gets around 106 mm of rain over 9.5 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 30% and peaks near 32% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
130
230
331
431
531
632
732
832
932
1032
1132
1232
1331
1431
1531
1631
1730
1830
1930
2030
2130
2230
2329
2429
2529
2629
2729
2829
2929
3029

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 32% of days. Sticky, muggy-or-worse air turns up on roughly 39% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1102831266
292731266
392631277
492532277
582532287
682432288
772432298
872333298
962333309
1062233309
1152233319
12522323110
13421323210
14421323210
15421323210
16422323210
17422323210
18423323110
19423323110
20424323010
21424323010
22425323010
23425322910
24426312910
25427312910
26427302910
27427302910
28328292910
29328293010
30328283011

Wind in September

Winds average 24 km/h in September.

Across September, daily wind ranges from about 24 km/h on the calmest days to 25 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202530
Wind speed (km/h)Feels
125breezy
225breezy
325breezy
425breezy
525breezy
625breezy
725breezy
825breezy
925breezy
1025breezy
1125breezy
1225breezy
1325breezy
1425breezy
1525breezy
1625breezy
1725breezy
1825breezy
1925breezy
2025breezy
2124breezy
2224breezy
2324breezy
2424breezy
2524breezy
2624breezy
2724breezy
2824breezy
2924breezy
3024breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 36 min at the start of September to 12 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 36 minutes over September. Sunrise moves from 6:53 AM to 6:25 AM, and sunset from 6:28 PM to 6:35 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.66:536:28
211.66:526:28
311.66:516:28
411.66:506:29
511.76:506:29
611.76:496:29
711.76:486:29
811.76:476:30
911.76:466:30
1011.86:456:30
1111.86:446:30
1211.86:436:31
1311.86:426:31
1411.86:416:31
1511.96:406:31
1611.96:396:32
1711.96:386:32
1811.96:376:32
1911.96:366:32
2012.06:356:33
2112.06:346:33
2212.06:336:33
2312.06:326:33
2412.06:316:34
2512.16:306:34
2612.16:296:34
2712.16:286:34
2812.16:276:35
2912.26:266:35
3012.26:256:35

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5 kWh/m².

For context, solar energy here swings from a low near 3.27 kWh/m² to a high of 6.69 kWh/m² in December across the year — September's 5 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.6Bright
44.6Bright
54.6Bright
64.7Bright
74.7Bright
84.7Bright
94.8Bright
104.8Bright
114.8Bright
124.9Bright
134.9Bright
144.9Bright
155.0Bright
165.0Bright
175.1Bright
185.1Bright
195.1Bright
205.2Bright
215.2Bright
225.3Bright
235.3Bright
245.3Bright
255.4Bright
265.4Bright
275.4Bright
285.5Bright
295.5Bright
305.5Bright
Planning a trip in September

Is September a good time to visit Nuku‘alofa?

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

6.9
Sightseeing
4th-best month of the year
5.2
Beach & pool
11th-best month of the year

September is a reasonable time to visit Nuku‘alofa for sightseeing.

What to pack for Nuku‘alofa in September

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

In September, Nuku‘alofa sees daytime highs around 23°C and nights near 22°C. Worth packing: light clothes, rain gear, sun protection and a windbreaker. About 10 days see rain.

light clothesrain gearsun protectiona windbreaker

Sea temperature near Nuku‘alofa in September

The nearest coast averages about 24°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in March at about 28°C and coldest in August near 24°C.

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

22°24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb28Warm
Mar28Warm
Apr27Warm
May26Warm
Jun25Warm
Jul24Warm
Aug24Refreshing
Sep24Refreshing
Oct24Warm
Nov25Warm
Dec26Warm

UV index in Nuku‘alofa in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Nuku‘alofa peaks around February 12 at about 16 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 23 at about 7 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeFeb 12UV 16Jun 23UV 7
UV index (midday)Level
Jan15Extreme
Feb16Extreme
Mar14Extreme
Apr10Very high
May7Very high
Jun7High
Jul7High
Aug8Very high
Sep11Extreme
Oct14Extreme
Nov13Extreme
Dec13Extreme
Location & terrain

Where is Nuku‘alofa?

Nuku‘alofa sits at 21.1°S, 175.2°W, 1 m above sea level, in Tonga. The nearest listed city is Alofi, 598 km away.

Topography around Nuku‘alofa

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

Within 3 km, the terrain around Nuku‘alofa has only modest variations in elevation — a maximum elevation change of 21 m around an average of 3 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 73 m; within 80 km, significant variations in elevation — a maximum elevation change of 299 m.

The land around Nuku‘alofa is covered by water (52%) and artificial surfaces (20%) within 3 km, water (68%) within 16 km, and water (97%) within 80 km.

3 km
21 m
16 km
73 m
80 km
299 m
treesgrasslandartificial surfaceswatermangroves
September weather nearby: Alofi 598 km · Levuka 668 km · Nasinu 741 km · Suva 746 km · Lami 749 km · Labasa 775 km · Sigatoka 833 km · Nadi 858 km

Tonga travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type I
230 V · 50 Hz
Prices
≈ 75% of US
price level, 2025
GDP per capita
$6,547
2025
Safe drinking water
30%
of population, 2024
Homicide rate
0.9
per 100k, 2019
Road deaths
33
per 100k/yr, 2019
Income group
Upper middle
World Bank
Religion
Protestant 64%Church of Jesus Christ 20%Roman Catholic 14%other 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 Nuku‘alofa (-21.1368°, -175.2011°, elevation 1 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).