Climate and average weather in Nuku‘alofa
In Nuku‘alofa, the weather is muggy, warm, wet, and partly cloudy and remarkably steady, with daytime highs holding near warm levels all year. The wettest stretch peaks around March.
Over the course of the year, the temperature in Nuku‘alofa typically varies from 21°C to 27°C, and is rarely below 20°C or above 28°C. February is the hottest month of the year, while August is the coldest.
Based on the travel score, the best times of year to visit Nuku‘alofa for warm-weather activities are from early January to late January and late March to late December.
- Hottest
- Feb
- 27°
- Coldest
- Aug
- 21°
- Wettest
- Mar
- 230 mm
- Driest
- Oct
- 93 mm
- Rain / yr
- 1612 mm
- 139 wet days
- Daylight
- 10.7–13.3 h
- shortest–longest
- Elevation
- 1 m
- 21.1°S
- Clearest
- Sep
- 59% cloud
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.
Nuku‘alofa weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late March to late December.
Temperature through the year
Daily average highs and lows in Nuku‘alofa, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
Temperatures in Nuku‘alofa stay fairly even through the year, without a distinct hot or cool season. The warmest month is February, with an average high of 27°C and low of 26°C; the coolest is August, with an average low of 21°C and high of 23°C.
Days typically run about 1°C warmer than nights year-round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 26 | 27 | 27 | 26 | 25 | 24 | 23 | 23 | 23 | 23 | 25 | 26 |
| Avg low (°C) | 25 | 26 | 26 | 25 | 24 | 23 | 22 | 21 | 22 | 22 | 23 | 25 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 26 | 25 |
| Feb | 27 | 26 |
| Mar | 27 | 26 |
| Apr | 26 | 25 |
| May | 25 | 24 |
| Jun | 24 | 23 |
| Jul | 23 | 22 |
| Aug | 23 | 21 |
| Sep | 23 | 22 |
| Oct | 23 | 22 |
| Nov | 25 | 23 |
| Dec | 26 | 25 |
Average hourly temperature in Nuku‘alofa
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on February afternoons, near 27°C, and coldest before dawn in August, near 21°C.
Nuku‘alofa weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 26° / 25° | 195 | 15.5 | 13.1 | 5.7 |
| Feb | 27° / 26° | 203 | 16.5 | 12.7 | 5.3 |
| Mar | 27° / 26° | 230 | 18.3 | 12.1 | 5.3 |
| Apr | 26° / 25° | 167 | 13.4 | 11.5 | 6.0 |
| May | 25° / 24° | 103 | 10.1 | 11 | 6.8 |
| Jun | 24° / 23° | 106 | 8.8 | 10.7 | 7.0 |
| Jul | 23° / 22° | 96 | 8.4 | 10.8 | 7.0 |
| Aug | 23° / 21° | 109 | 8.6 | 11.3 | 6.9 |
| Sep | 23° / 22° | 106 | 9.5 | 11.9 | 6.9 |
| Oct | 23° / 22° | 93 | 8.5 | 12.5 | 7.1 |
| Nov | 25° / 23° | 99 | 9.2 | 13 | 6.9 |
| Dec | 26° / 25° | 105 | 12.1 | 13.3 | 6.4 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Nuku‘alofa gets about 1612 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.
The wetter season lasts 4.6 months, from around Dec 13 to May 2, peaking in February at about 61% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jul 18.
March is the wettest month by volume, with 230 mm over about 18 wet days; October is the driest, with 93 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 50 | 60 | 58 | 45 | 33 | 30 | 27 | 28 | 30 | 27 | 31 | 39 |
| Rain days | 16 | 17 | 18 | 13 | 10 | 9 | 8 | 9 | 10 | 9 | 9 | 12 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 50 | 16 |
| Feb | 60 | 17 |
| Mar | 58 | 18 |
| Apr | 45 | 13 |
| May | 33 | 10 |
| Jun | 30 | 9 |
| Jul | 27 | 8 |
| Aug | 28 | 9 |
| Sep | 30 | 10 |
| Oct | 27 | 9 |
| Nov | 31 | 9 |
| Dec | 39 | 12 |
Monthly rainfall
Over a full year, Nuku‘alofa collects about 1612 mm of rain across 139 wet days — roughly 134 mm in an average month.
It doesn’t fall evenly. March is the wettest month with 230 mm, while October is the driest at just 93 mm. The three wettest months alone bring about 39% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 195 | 203 | 230 | 167 | 103 | 106 | 96 | 109 | 106 | 93 | 99 | 105 |
| Rain days | 16 | 17 | 18 | 13 | 10 | 9 | 8 | 9 | 10 | 9 | 9 | 12 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 195 | 16 |
| Feb | 203 | 17 |
| Mar | 230 | 18 |
| Apr | 167 | 13 |
| May | 103 | 10 |
| Jun | 106 | 9 |
| Jul | 96 | 8 |
| Aug | 109 | 9 |
| Sep | 106 | 10 |
| Oct | 93 | 9 |
| Nov | 99 | 9 |
| Dec | 105 | 12 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Nuku‘alofa, the average share of the sky covered by clouds shows mild seasonal variation over the course of the year.
The clearer part of the year begins around July 7 and lasts for 3.3 months, ending around October 14. The clearest month is September, when the sky is clear, mostly clear, or partly cloudy 51% of the time on average.
The cloudier part of the year begins around February 23 and lasts for 1.0 months, ending around March 25. The cloudiest month is June, when it is overcast or mostly cloudy 57% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 46 | 47 | 43 | 47 | 45 | 43 | 48 | 50 | 51 | 48 | 47 | 48 |
| Cloudier (%) | 54 | 53 | 57 | 53 | 55 | 57 | 52 | 50 | 49 | 52 | 53 | 52 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 46 | 54 |
| Feb | 47 | 53 |
| Mar | 43 | 57 |
| Apr | 47 | 53 |
| May | 45 | 55 |
| Jun | 43 | 57 |
| Jul | 48 | 52 |
| Aug | 50 | 50 |
| Sep | 51 | 49 |
| Oct | 48 | 52 |
| Nov | 47 | 53 |
| Dec | 48 | 52 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around January 1, brings about 13 h 18 min of light; the shortest, around June 10, only 10 h 42 min — a swing of roughly 2 h 36 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 13.1 | 12.7 | 12.1 | 11.5 | 11.0 | 10.7 | 10.8 | 11.3 | 11.9 | 12.5 | 13.0 | 13.3 |
| Sunrise (AM) | 6:15 | 6:34 | 6:46 | 6:56 | 7:07 | 7:19 | 7:22 | 7:07 | 6:39 | 6:11 | 5:55 | 5:59 |
| Sunset (PM) | 7:25 | 7:17 | 6:55 | 6:26 | 6:07 | 6:03 | 6:11 | 6:23 | 6:32 | 6:41 | 6:57 | 7:15 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 13.1 | 6:15 | 7:25 |
| Feb | 12.7 | 6:34 | 7:17 |
| Mar | 12.1 | 6:46 | 6:55 |
| Apr | 11.5 | 6:56 | 6:26 |
| May | 11.0 | 7:07 | 6:07 |
| Jun | 10.7 | 7:19 | 6:03 |
| Jul | 10.8 | 7:22 | 6:11 |
| Aug | 11.3 | 7:07 | 6:23 |
| Sep | 11.9 | 6:39 | 6:32 |
| Oct | 12.5 | 6:11 | 6:41 |
| Nov | 13.0 | 5:55 | 6:57 |
| Dec | 13.3 | 5:59 | 7:15 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Nuku‘alofa averages about 9 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 7 and 10 days.
The sunnier stretch runs 1.8 months, from around Aug 28 to Oct 22. The sunniest month is October, with roughly 9 sunny days (mixed).
The greyest month is June, down near 7 sunny days — about 20% fewer than the October peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 9 | 8 | 8 | 9 | 8 | 7 | 9 | 9 | 9 | 9 | 8 | 9 |
| Sky | Mixed | Mixed | Mixed | Mixed | Gloomy | Gloomy | Mixed | Mixed | Mixed | Mixed | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 9 | Mixed |
| Feb | 8 | Mixed |
| Mar | 8 | Mixed |
| Apr | 9 | Mixed |
| May | 8 | Gloomy |
| Jun | 7 | Gloomy |
| Jul | 9 | Mixed |
| Aug | 9 | Mixed |
| Sep | 9 | Mixed |
| Oct | 9 | Mixed |
| Nov | 8 | Mixed |
| Dec | 9 | Mixed |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Nuku‘alofa, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 7.1 months, from around October 25 to May 29. The muggiest month is January, when the air feels humid, muggy or worse about 100% of the time.
The most comfortable stretch runs from around May 30 to October 24, and August is the most comfortable month — the air is dry or comfortable 38% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 0 | 0 | 0 | 0 | 0 | 2 | 7 | 9 | 5 | 2 | 0 | 0 |
| Comfortable (%) | 0 | 0 | 0 | 2 | 9 | 20 | 29 | 29 | 25 | 18 | 7 | 2 |
| Humid (%) | 5 | 2 | 2 | 8 | 26 | 26 | 29 | 28 | 31 | 28 | 20 | 10 |
| Muggy (%) | 19 | 10 | 14 | 33 | 37 | 35 | 26 | 27 | 30 | 34 | 37 | 30 |
| Oppressive (%) | 62 | 66 | 65 | 52 | 28 | 16 | 8 | 7 | 9 | 18 | 36 | 56 |
| Miserable (%) | 15 | 22 | 20 | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| Jan | 0 | 0 | 5 | 19 | 62 | 15 |
| Feb | 0 | 0 | 2 | 10 | 66 | 22 |
| Mar | 0 | 0 | 2 | 14 | 65 | 20 |
| Apr | 0 | 2 | 8 | 33 | 52 | 5 |
| May | 0 | 9 | 26 | 37 | 28 | 0 |
| Jun | 2 | 20 | 26 | 35 | 16 | 0 |
| Jul | 7 | 29 | 29 | 26 | 8 | 0 |
| Aug | 9 | 29 | 28 | 27 | 7 | 0 |
| Sep | 5 | 25 | 31 | 30 | 9 | 0 |
| Oct | 2 | 18 | 28 | 34 | 18 | 0 |
| Nov | 0 | 7 | 20 | 37 | 36 | 0 |
| Dec | 0 | 2 | 10 | 30 | 56 | 3 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Nuku‘alofa is typically breezy, near 24 km/h, and varies little with the seasons.
The windier part of the year lasts 4.1 months, from around Apr 7 to Aug 8. The windiest month is April, averaging about 25 km/h (breezy).
The calmer part of the year runs from around Jan 14 to Apr 6, with February the calmest month at about 23 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 24 | 23 | 23 | 25 | 25 | 25 | 25 | 25 | 25 | 25 | 24 | 24 |
| Feels | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy | breezy |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 24 | breezy |
| Feb | 23 | breezy |
| Mar | 23 | breezy |
| Apr | 25 | breezy |
| May | 25 | breezy |
| Jun | 25 | breezy |
| Jul | 25 | breezy |
| Aug | 25 | breezy |
| Sep | 25 | breezy |
| Oct | 25 | breezy |
| Nov | 24 | breezy |
| Dec | 24 | breezy |
Best time to visit Nuku‘alofa
To characterize how pleasant the weather is in Nuku‘alofa throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around late December, Nuku‘alofa is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Nuku‘alofa for general outdoor tourist activities is from late March to late January, with a peak score in the last week of June.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 5.7 | 5.3 | 5.3 | 6.0 | 6.8 | 7.0 | 7.0 | 6.9 | 6.9 | 7.1 | 6.9 | 6.4 |
| Rating | good | fair | fair | good | good | good | good | good | good | good | good | good |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 5.7 | good |
| Feb | 5.3 | fair |
| Mar | 5.3 | fair |
| Apr | 6.0 | good |
| May | 6.8 | good |
| Jun | 7.0 | good |
| Jul | 7.0 | good |
| Aug | 6.9 | good |
| Sep | 6.9 | good |
| Oct | 7.1 | good |
| Nov | 6.9 | good |
| Dec | 6.4 | good |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, Nuku‘alofa suits hot-weather activities for most of the year, with a peak score in the last week of November.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Nuku‘alofa, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
Nuku‘alofa packs about the same all year — highs hold near 27°C. Across the year the things worth having are light clothes, rain gear, sun protection and a windbreaker.
In February, Nuku‘alofa sees daytime highs around 27°C and nights near 26°C. Pack rain gear and sun protection. Worth having: light clothes and a windbreaker. About 17 days see rain.
Sea temperature near Nuku‘alofa
Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.
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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 27 | 28 | 28 | 27 | 26 | 25 | 24 | 24 | 24 | 24 | 25 | 26 |
| Comfort | Warm | Warm | Warm | Warm | Warm | Warm | Warm | Refreshing | Refreshing | Warm | Warm | Warm |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 27 | Warm |
| Feb | 28 | Warm |
| Mar | 28 | Warm |
| Apr | 27 | Warm |
| May | 26 | Warm |
| Jun | 25 | Warm |
| Jul | 24 | Warm |
| Aug | 24 | Refreshing |
| Sep | 24 | Refreshing |
| Oct | 24 | Warm |
| Nov | 25 | Warm |
| Dec | 26 | Warm |
UV index (midday) in Nuku‘alofa by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 15 | 16 | 14 | 10 | 7 | 7 | 7 | 8 | 11 | 14 | 13 | 13 |
| Level | Extreme | Extreme | Extreme | Very high | Very high | High | High | Very high | Extreme | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 15 | Extreme |
| Feb | 16 | Extreme |
| Mar | 14 | Extreme |
| Apr | 10 | Very high |
| May | 7 | Very high |
| Jun | 7 | High |
| Jul | 7 | High |
| Aug | 8 | Very high |
| Sep | 11 | Extreme |
| Oct | 14 | Extreme |
| Nov | 13 | Extreme |
| Dec | 13 | Extreme |
Average hourly UV index in Nuku‘alofa
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in February the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 7 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 9 | 9 | 8 | 7 | 6 | 5.5 | 6 | 6.5 | 7.5 | 8.5 | 8.5 | 8.5 |
| UV ≥ 6 (h/day) | 7 | 7 | 6.5 | 5 | 3 | 2 | 2.5 | 3.5 | 5.5 | 6.5 | 6.5 | 6.5 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 9 | 7 |
| Feb | 9 | 7 |
| Mar | 8 | 6.5 |
| Apr | 7 | 5 |
| May | 6 | 3 |
| Jun | 5.5 | 2 |
| Jul | 6 | 2.5 |
| Aug | 6.5 | 3.5 |
| Sep | 7.5 | 5.5 |
| Oct | 8.5 | 6.5 |
| Nov | 8.5 | 6.5 |
| Dec | 8.5 | 6.5 |
Growing season
Nuku‘alofa is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Nuku‘alofa banks about 5,151 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around February.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 489 | 455 | 501 | 463 | 439 | 397 | 383 | 373 | 366 | 400 | 419 | 467 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 489 |
| Feb | 455 |
| Mar | 501 |
| Apr | 463 |
| May | 439 |
| Jun | 397 |
| Jul | 383 |
| Aug | 373 |
| Sep | 366 |
| Oct | 400 |
| Nov | 419 |
| Dec | 467 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Nuku‘alofa receives about 5.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.3 and 6.9 kWh/m².
The brighter stretch of the year lasts 6.3 months, from around Sep 19 to Mar 29. The brightest month is December, averaging about 6.8 kWh/m² (intense).
The dimmest month is June, down near 3.3 kWh/m² — roughly 51% less than the December peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.6 | 6.1 | 5.4 | 4.6 | 3.8 | 3.3 | 3.4 | 4.0 | 5.0 | 5.9 | 6.4 | 6.7 |
| Level | Intense | Intense | Bright | Bright | Moderate | Moderate | Moderate | Bright | Bright | Bright | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 6.6 | Intense |
| Feb | 6.1 | Intense |
| Mar | 5.4 | Bright |
| Apr | 4.6 | Bright |
| May | 3.8 | Moderate |
| Jun | 3.3 | Moderate |
| Jul | 3.4 | Moderate |
| Aug | 4.0 | Bright |
| Sep | 5.0 | Bright |
| Oct | 5.9 | Bright |
| Nov | 6.4 | Intense |
| Dec | 6.7 | Intense |
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.
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
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).