The Best Time to Scuba Dive in Tonga(c) Tonga Ministry of Tourism
The Best Time to Scuba Dive in Tonga

The Best Time to Dive in Tonga

(c) Tonga Ministry of Tourism

The Scuba Diving Seasons in Tonga

Unlike many places in the world, Tonga doesn’t have a “bad” time to scuba dive. The visibility is pretty darn good all year round, averaging around 30 m (100 ft) in both summer and winter. However, if you are chasing whales, looking to escape the crowds, or just want the conditions a little bit clearer, warmer or whatever, then there will be the best time to scuba dive in Tonga. Get more advice on the Tonga diving seasons in the guide below.

5 Facts About Scuba Diving in Tonga

  1. The water temperature in Tonga is 21-28°C (70-82°F) year-round for comfortable diving
  2. The visibility is rarely less than 20 m (66 ft) but more commonly 30 m+ (100 ft)
  3. Be sure to book dive tours well in advance during the whale season (July to October) as some dive operators are also busy running whale swimming tours at this time
  4. Tonga has an array of amazing dive sites, which you can check out in the 10 Best Dive Sites in Tonga
  5. Sights on dives can include sharks, tuna and manta rays around 1,500 species of fish and 700 species of coral.

The Best Time to Scuba Dive in Tonga(c) Tonga Ministry of Tourism

Winter Diving in Tonga

Tonga’s winter season, also known as the dry season, runs between May and October. However, winter in Tonga is far from “wintery” with sea temperatures typically around 21°C (69°F) and air temperatures between 19 and 29°C (66-84°F). A 5 mm full-length wetsuit is usually comfortable for these winter months, along with a warm layer for boat rides after getting out of the water.

Water Visibility in Winter

The winter gets its “dry season” name due to the less precipitation that the South Pacific receives during the months of May and October. The average rainfall is around 110 mm (3.9 in) per month and sees less surface run-off into the ocean. This often results in some of the clearest waters Tonga experiences, often being 30 m+ (100 ft) up to as much as 70 m (230 ft) on some occasions!

The Whale Season

If your goal is to swim with humpback whales, then the winter season is the best time to try scuba diving in Tonga. Whales can only be found in Tonga’s waters between July and October (with a little more of an extended season in Tongatapu and ‘Eua). On the downside, there are very limited operators who offer scuba diving trips during the whale season, as most prioritise whale swimming tours during this time. The odd exception can be found in the 5 Best Dive Shops & Operators in Tonga, while more about the whales is listed in The Guide to Whale Swimming in Tonga.

More About the Winter Season Climate

Learn more about the seasons in Tonga in Tonga Weather, Seasons & Climate + Tonga Weather by Month. Plus, get more advice on planning a scuba trip to the islands with The Guide to Scuba Diving in Tonga.

The Best Time to Scuba Dive in Tonga(c) Tonga Ministry of Tourism

Summer Diving in Tonga

Summer in Tonga runs from November to April and is also known as the wet season. This time is usually hotter and more humid in Tonga, making scuba diving a pretty relieving experience from the heat. Sea temperatures are typically around 24°C (75°F), while air temperatures are between 23 and 31°C (74-88°F). A 3 mm full-length or a shortie wetsuit is usually suitable for these months.

Water Visibility in the Summer Season

November to April also falls into the wet season and the cyclone season in the South Pacific, where the average precipitation per month is 210 mm (8.3 in). As a result, these months tend to have slightly less water visibility but still average around 30 m (98 ft) and rarely drop below 20 m (66 ft).

Tourist Low Season

An advantage of a scuba diving trip in summer in Tonga is that it’s the tourist low season. This means that you can often find yourself in resorts with little to no one around, discounts on accommodations and sometimes even flights, and having entire dive sites to yourself (and your buddy and dive instructor, of course).

More advantages for travelling at this time of the year can be found in the 10 Reasons to Travel in the Low Season in Tonga.

More About the Best Time to Scuba Dive in Tonga

That’s it for the best time to dive in Tonga but not the end of our scuba diving advice! Check out the following guides for bubbles of fun:

Finally, if there’s anything we’ve missed, you’re likely to find it in The Guide to Scuba Diving in Tonga, as well as The Best Time to Visit Tonga.


Laura (Lola) S.

This article was reviewed and published by Laura, editor in chief and co-founder of Tonga Pocket Guide. Since arriving solo in the South Pacific over 10 years ago with nothing but a backpack and a background in journalism, her mission has been to show the world how easy (and awesome) it is to explore a paradise such as Tonga. She knows the islands inside-out and loves sharing tips on how best to experience Tonga’s must-dos and hidden gems. Laura is also editor of several other South Pacific travel guides.

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