Rarotonga & the Cook Islands Weather in July

Last Updated: 16 June, 2025

What is the Weather Like in Rarotonga and the Cook Islands in July?

What does winter look like in Rarotonga and the Cook Islands? Well, think balmy days of around 25°C (77°F), slightly cooler evenings and dry days most of the time. No wonder July is one of the most popular times to visit the islands!

The weather and sea temperatures are ideal for engaging in almost any activity in the Cook Islands, including snorkelling, scuba diving, and even spotting humpback whales during their annual migration to the Cook Islands. Because of the popularity of Rarotonga and Aitutaki (and limited accommodation on other islands), it’s best to book your spot early during this busy tourist season.

Otherwise, check out more tips about the climate in this guide to the Rarotonga and Cook Islands weather in July.

Before we jump into this weather guide for July, be sure to bookmark Rarotonga & the Cook Islands Weather, Seasons & Climate and The Best Time to Visit the Cook Islands for more advice.

6 Tips for Visiting the Cook Islands in July

July is part of the peak season in Rarotonga and the Cook Islands, so book accommodation in advance to avoid disappointment.
The evenings feel considerably cooler than during the day, so be sure to pack a light jacket – this will be useful on boat trips too.
While July is considered the dry season, be prepared for rain at any time.
Apply high-factor reef-safe sunscreen regularly.
It is possible to spot humpback whales migrating through the Cook Islands in July. See the 10 Best Places for Whale Watching in the Cook Islands for more information.
Be aware that the first Friday of the month is a public holiday, Ra o te Ui Ariki, so some businesses will be closed on this day.

Rarotonga & the Cook Islands Weather in July

Typical Temperatures in July

Warm, balmy and with mild sea temperatures, the Cook Islands sure has a good winter season. The average maximum temperature in July is 25°C (77°F), which is often extremely comfortable and soothing throughout the day.

Evenings are a little cooler, however, where it’s best to have an extra layer, especially when combined with the sea breeze! The average nighttime low is 19°C (66°F).

Temperatures Across the Cook Islands

Rarotonga – The average maximum temperature is 25°C (77°F) and the minimum average temperature is 19°C (66°F)
Aitutaki – The average maximum temperature is 27°C (81°F) and the minimum average temperature is 21°C (70°F)
Mangaia – The average maximum temperature is 25°C (77°F) and the minimum average temperature is 19°C (66°F)
Mitiaro – The average maximum temperature is 27°C (81°F) and the minimum average temperature is 20°C (68°F)
Manihiki (North) – The average maximum temperature is 30°C (86°F) and the minimum average temperature is 24°C (75°F)
Penrhyn (North) – The average maximum temperature is 31°C (88°F) and the minimum average temperature is 24°C (75°F).

Sea Temperature in July

The Cook Islands has warm sea temperatures all year round. Even in winter, the sea temperature rarely drops below 25°C (77°F).

Hours of Sun in July

During July, the Cook Islands’ daylight hours are 11 hours long – pretty long considering we are in the winter months. Visitors can expect an average of 2 hrs 30 mins of bright sunshine per day, making July one of the sunniest months in the Cook Islands.

UV Levels During July

The UV levels in July in the Cook Islands are pretty mild with a level of 6 UV index around midday. Nevertheless, it’s still a good idea to apply high-factor sunscreen.

For advice on sunscreen, check out The Best Sunscreens for the Cook Islands + Sun Protection Tips.

Sunrise and Sunset During July

July has daylight hours lasting about 11 hours a day in the Cook Islands.

Sunrise: 7:17 am at the beginning of July and 7:11 am at the end of June
Sunset: 6:09 pm at the beginning of July and 6:20 pm at the end of June.

Learn about the local time zone in What is the Rarotonga & the Cook Islands Time Zone?

Rainfall in July

Rainfall is quite minimal in the Cook Islands in the month of July. Although there is an average of 102 mm (4 in) of rain, there is typically only 5 days of rainfall throughout the month. Showers are heavy but don’t last for too long.

Average Rainfall Across the Cook Islands

Rarotonga – The average rainfall in July is 102 mm (4 in)
Aitutaki – The average rainfall in July is 81 mm (3.2 in)
Mangaia – The average rainfall in July is 102 mm (4 in)
Mitiaro – The average rainfall in July is 68 mm (2.7 in)
Manihiki (North) – The average rainfall in July is 115 mm (4.5 in)
Penrhyn (North) – The average rainfall in July is 124 mm (4.9 in).

Tropical Storms in July

The South Pacific cyclone season starts in November and ends in April. As such, July is one of the best months to avoid tropical cyclones in the Cook Islands, with a very low risk of tropical storms developing.

Other months with a low risk of tropical storms in the Cook Islands include June, August, and September. Find out more about tropical storms in our guide, Cyclone Safety in the Cook Islands.

Best Places to Visit in the Cook Islands in July

Any part of the Cook Islands is stunning to visit during this warm, dry and pretty quiet time of the year. While we list all of the Cook Islands in What are the 15 Islands in the Cook Islands? for inspiration, a few places worth checking out in the Cook Islands during July include:

Rarotonga – Rarotonga is a hotspot for island holidays in the Cook Islands and for good reason. The largest island in the cooks has a high-quality tourism infrastructure, including resorts and tours. It’s also the arrival island for international flights, making for an easy fly-and-flop getaway. Find out more about what Rarotonga is all about in the 50 Best Things to Do on Rarotonga.

Aitutaki – For similar reasons as visiting Rarotonga, Aitutaki is worth visiting in July for its developed tourist scene. However, Aitutaki is still much less visited than Rarotonga, effortlessly offering a tranquil South Seas getaway. Learn more about what to do in Aitutaki in the 20 Best Things to Do on Aitutaki.

Mauke – Escape the hustle and bustle of the Cook Islands’ busier islands and visit one of the lesser-visited paradises, Mauke. A tiki tour around the island will bring you to small beaches and photogenic coastal archways (formed by limestone, of course). But no visitor can miss out on a swim in the impressive Vai Tano Cave. Learn more about an island escape to Mauke in the 15 Best Things to Do in Mauke.

Again, any of the islands are decent to visit during July, so we recommend researching more on the subject using A Guide to the Best Islands of the Cook Islands.

July Packing List for Rarotonga and the Cook Islands

Be prepared for the Cook Islands in July by packing these few seasonal essentials:

Light clothing layers (preferably linen, bamboo or merino so it is super light – we like the sustainable bamboo clothing of Moso Morrow)
Light long-sleeved tops/jackets (to take the edge off those slightly cooler nights or to keep warm after boat trips)
Light pants/trousers/skirt (to cover the knees when appropriate – church service or to protect from mosquitoes when hiking, for example)
Sunhat
Sunglasses
Swimwear
Rash vest (we like the UV-protecting Sharkskin rashies)
Closed walking shoes
Flip-flops/jandals/sandals
Sarong (pāreu – available in the Cook Islands; it’s a good way to cover up when exploring the towns after swimming)
Insect repellent
High-factor sunscreen (that’s reef-safe and water-resistant).

Get more ideas on what to pack with our guide, What to Pack for Rarotonga & the Cook Islands: Cook Islands Packing List.

More About the Weather in Rarotonga and Cook Islands in July

That’s it for our complete guide to the weather and climate in Rarotonga and the Cook Islands in July. Check out the following articles for more weather advice:

Finally, enjoy a comprehensive guide to planning a trip to the Cook Islands in The Best Cook Islands Travel Guide.

Sources:

The information in this guide has been compiled from our extensive research, travel and experiences across the Cook Islands and the South Pacific, accumulated over more than a decade of numerous visits to each destination. Additional sources for this guide include the following:

Cook Islands Tourism Corporation (General travel advice - Updated [2025])
Cook Islands Tourism Industry Council (Tourism trade association - Updated [2025])
Ministry of Foreign Affairs and Immigration (Visa and immigration advice - Updated [2025])
Ministry of Finance & Economic Management (Border restrictions advice - Updated [2025])
Ministry of Agriculture (Biosecurity advice - Updated [2025])
Cook Islands Meteorological Service (Weather forecast and warnings - Updated [2025])
Cook Islands Statistics Office (Statistics and travel data - Updated [2025])
Ministry of Transport (Transport operators and licenses - Updated [2025])
SPTO (Pacific tourism advice - Updated [2025])
Safe Travel (New Zealand travel advisory for the Cook Islands - Updated [2025])
Smart Traveller (Australia travel advisory for the Cook Islands - Updated [2025])

At Cook Islands Pocket Guide, we uphold strict editorial standards to ensure accurate and quality content.

About the Author

Robin C.

This article was reviewed and published by Robin, the co-founder of Cook Islands 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 Cook Islands Tourism Corporation, a local government body representing the tourism industry. 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.

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