The Weather in Tonga: Month-by-Month
When you’re looking to escape to a tropical paradise, the weather is kind of important! Tonga is a tropical island archipelago with two seasons, yet never really experiences cold weather. Nevertheless, there are significant changes in rainfall and humidity throughout the year. So to answer the question: what is the weather like in Tonga? Check out our guide to the Tonga weather by month!
The Tonga Climate and Seasons: The Tonga Weather Year Round
Tonga has a tropical climate with two distinct seasons:
- Wet/summer season: December to April
- Dry/winter season: May to November
The average maximum temperature in the wet season is 29°C (84°F), while the maximum average in the dry season is 24°C (75°F).
Learn more about the seasons in Tonga, including the tourist seasons and the best seasons for certain activities, in our guide, What are the Seasons in Tonga?
January Weather in Tonga
The year gets off to a hot and humid start in Tonga, in the midst of the wet season. It’s also the cyclone season in the South Pacific, so it’s best to be aware of cyclone warnings – see our Tonga cyclone guide for more details. Otherwise, the country is vibrant with New Year and Chinese New Year (changeable) celebrations, particularly in Nuku’alofa.
Average temperature: 30°C/86°F in the day, 23°C/74°F at night
Average sea temperature: 28°C/82°F
Average rainfall: 174mm/6.9″
Daylight hours: 13 hours
For more in-depth information, see our complete guide to the Tonga Weather in January.
February Weather in Tonga
It’s still the wet season in Tonga, with some of the heaviest rainfall experienced in February. Temperatures are warm and humid, but at least the days are long and there are still plenty of sunshine hours for those seeking some sun. February is also considered the low season, which is a cheap and quiet time to experience the islands. See the 10 Reasons to Travel in the Low Season in Tonga for more benefits.
Average temperature: 31°C/88°F in the day, 24°C/75°F at night
Average sea temperature: 28°C/83°F
Average rainfall: 210mm/8.3″
Daylight hours: 13 hours
For more in-depth information, see our complete guide to the Tonga Weather in February.
March Weather in Tonga
The wet season continues, with still the slight risk of cyclones developing. The northern groups of islands, like Vava’u and The Niues, experience their highest rainfall and temperatures of the year, while the middle islands of Ha’apai are not close behind.
Average temperature: 31°C/88°F in the day, 23°C/74°F at night
Average sea temperature: 28°C/83°F
Average rainfall: 206mm/8.1″
Daylight hours: 12 hours
For more in-depth information, see the complete guide to the Tonga Weather in March.
April Weather in Tonga
April is the final month of the wet season, still bringing some “April showers” along with it. Temperatures steadily start to cool in the southern islands, such as Tongatapu and ‘Eua. It’s also the last month of the cyclone season. Humidity levels fall also, making it easier to breathe again!
Average temperature: 30°C/86°F in the day, 22°C/69°F at night
Average sea temperature: 28°C/82°F
Average rainfall: 165mm/6.5″
Daylight hours: 12 hours
For more in-depth information, see our full guide to the Tonga Weather in April.
May Weather in Tonga
May is the official start to the dry season, where temperatures start to get cooler and the humidity drops. There are fewer rain days but when it does rain, it’s usually heavy showers. The UV levels are also not quite as intense as in summer, averaging around 7 UV index at midday. May is a good time to visit “the Kingdom” before the tourist crowds arrive. May is also the beginning of the sailing season in Tonga.
Average temperature: 30°C/86°F in the day, 20°C/68°F at night
Average sea temperature: 27°C/80°F
Average rainfall: 111mm/4.4″
Daylight hours: 11 hours
For more in-depth information, see our complete guide to the Tonga Weather in May.
June Weather in Tonga
The dry season really kicks into gear with cooler and much drier days than what’s experienced in summer. June 4th is a public holiday, while the end of June is when the first humpback whales can be seen in Tonga’s waters for the calving and mating season. Sea temperatures are also dropping but still warm enough for a comfortable swim. Learn more about the whale season in The Guide to Whale Swimming in Tonga.
Average temperature: 29°C/84°F in the day, 20°C/67°F at night
Average sea temperature: 26°C/78°F
Average rainfall: 95mm/3.7″
Daylight hours: 11 hours
For more in-depth information, see the complete guide to the Tonga Weather in June.
July Weather in Tonga
July is a popular time to be in Tonga, with the start of the whale swimming season and the weather becoming more and more appealing for those wishing to escape the cold winter of their own country. July 4th is a public holiday for the King’s birthday, while the only other reason shops and services will close down will be for the usual Sunday rules.
Average temperature: 29°C/84°F in the day, 18°C/65°F at night
Average sea temperature: 25°C/76°F
Average rainfall: 95mm/3.7″
Daylight hours: 11 hours
For more in-depth information, see the complete guide to the Tonga Weather in July.
August Weather in Tonga
August is one of Tonga’s coolest months, which is still hot enough for travellers to enjoy a tropical and sunny getaway. But you’ll be thankful for bringing a light jacket for the cooler evenings or when darting between the islands by boat. The whale season is still going strong, while snorkelling and scuba diving is also a popular thing to do at this time of the year.
Average temperature: 29°C/84°F in the day, 18°C/65°F at night
Average sea temperature: 24°C/75°F
Average rainfall: 117mm/4.6″
Daylight hours: 11 hours
For more in-depth information, see the complete guide to the Tonga Weather in August.
September Weather in Tonga
September is usually an ideal month for travellers in terms of the weather and the activities available in Tonga. The weather is warm but not too hot, mostly dry with usually 13 days of the month experiencing rain, and the whale season still going. It’s typically a little drier in Vava’u than it is in Tongatapu. September is also an ideal month for fishing in Tonga.
Average temperature: 29°C/84°F in the day, 19°C/66°F at night
Average sea temperature: 24°C/75°F
Average rainfall: 122mm/4.8″
Daylight hours: 12 hours
For more in-depth information, see the complete guide to the Tonga Weather in September.
October Weather in Tonga
The whale season comes to an end in October, but it’s still idyllic weather for most travellers. Days are long and mostly dry, especially in the northern islands of Vava’u and the Ha’apai group. The sea temperatures rise slightly, making it a good time for snorkelling and diving.
Average temperature: 29°C/84°F in the day, 20°C/67°F at night
Average sea temperature: 25°C/78°F
Average rainfall: 128mm/5″
Daylight hours: 13 hours
For more in-depth information, see the complete guide to the Tonga Weather in October.
November Weather in Tonga
November is the month where you can really feel the transition from the dry season to the wet season in Tonga. Days are getting hotter, it’s starting to get more humid, and the rain gets more frequent towards the end of the month. Nevertheless, it’s the tourist low season so it’s a good time to experience the last of the good weather before the wet season gets into full swing.
Average temperature: 30°C/86°F in the day, 21°C/70°F at night
Average sea temperature: 25°C/78°F
Average rainfall: 123mm/4.8″
Daylight hours: 13 hours
For more in-depth information, see the complete guide to the Tonga Weather in November.
December Weather in Tonga
The wet season is well and truly here, where downpours are often heavy but short before the sun comes back out again. Travel schedules between the islands are often cancelled or rescheduled due to bad weather. It’s also the cyclone season, so it’s best to be aware of the cyclone and weather warnings. There are plenty of public holidays where the country shuts down for Christmas and New Year, as well as King Tupou I Commemoration Day on the 7th.
Average temperature: 30°C/86°F in the day, 22°C/73°F at night
Average sea temperature: 27°C/80°F
Average rainfall: 175mm/6.9″
Daylight hours: 13 hours
For more in-depth information, see the complete guide to the Tonga Weather in December.
Frequently Asked Questions About the Weather and Climate in Tonga
To wrap up this guide to the climate in Tonga, here are a few frequently asked questions travellers have about the weather in Tonga.
What is the Coldest Temperature in Tonga?
The average coldest temperature in Tonga is 18°C/65°F, usually experienced in the dry season at night. However, the coldest temperature on record is 8.7°C/47°F which occurred in 1994.
Does Tonga Get Snow?
No, Tonga does not get snow.
What is the Hottest Month in Tonga?
The hottest month in Tonga is typically February or March.
How Much Sun Does Tonga Get?
Tonga has long days with a lot of sun. Daylight hours range from 10 to 13 hours throughout the year, while the average sunshine reaches 18 sunshine hours in Tonga’s summer (December to March).
Does it Get Cold in Tonga?
No, Tonga is a tropical country with warm temperatures all year round.
More About What the Weather is Like in Tonga
That’s it for our guide on what the weather is like in Tonga. For more Tonga climate and weather tips, check out the following guides:
- What are the Seasons in Tonga?
- The Complete Packing List for Tonga
- The Best Time of the Year to Visit Tonga
Finally, get even more tips for planning the perfect getaway in The Complete Travel Guide to Tonga and the 31 Tips for Travelling in Tonga.
Author
Robin C.
This article was reviewed and published by Robin, the co-founder of Tonga Pocket Guide. He has lived, worked and travelled across 16 different countries before settling in the South Pacific, so he knows a thing or two about planning the perfect trip in this corner of the world. Robin works and consults regularly with the Ministry of Tourism of Tonga. Robin is also the co-founder of several other South Pacific travel guides and is a regular host of webinars with the South Pacific Tourism Organisation.