Rarotonga & the Cook Islands Weather in December

© David Kirkland - SPTO

Typical Temperatures in December

It’s getting hot! Although not as hot as the first few months of the year, December sees a real shift in temperature. December is part of the summer season in the Cook Islands, with the maximum daytime temperature averaging around 28°C / 82°F while the minimum average nighttime temperature is 22°C / 73°F. However, it can often feel a lot warmer with the high humidity experienced throughout the month. Sea temperatures are high too, giving further reason to jump in the water… Like if you needed a reason anyway!

Temperatures Across the Cook Islands

• Rarotonga – The average maximum temperature is 28°C / 82°F and the minimum average temperature is 22°C / 69°F
• Aitutaki – The average maximum temperature is 29°C / 84°F and the minimum average temperature is 23°C / 73°F
• Mangaia – The average maximum temperature is 28°C / 82°F and the minimum average temperature is 22°C / 72°F
• Mitiaro – The average maximum temperature is 29°C / 84°F and the minimum average temperature is 23°C / 73°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 25°C / 77°F.

Sea Temperature in December

The Cook Islands’ sea temperatures are warm and comfortable for swimming in all year round. In December, the temperature of the sea is on the rise, usually at around 26°C / 79°F.

© Dylan Harrison - Cook Islands Tourism

Hours of Sun in December

December will not disappoint when it comes to the sun. The days are long and hot and the sun rises early in the morning. Early birds will get to do plenty during the cool morning, while easily finding ways to cool down by the pool or by swimming in a lagoon when the sun reaches its zenith.

An average day in the Cook Islands in December lasts about 13 hours and features up to 7.5 hours of bright sunshine hours, usually around midday. Applying sunscreen, wearing sunglasses and a sunhat is a must at this time of the year. Plus, it’s a Christmas look that will make everybody jealous back at the office!

UV Levels During December

As mentioned earlier, UV levels in December are at their highest, peaking at 11+ on the hottest days. Those levels are classified as “extreme” meaning that tourists are advised to apply sunscreen regularly; every couple of hours or after going in the water. For the palest skins, consider investing in UV protective T-shirts as well – they are a great way to deal with this kind of sun.

We’ve got a lot of information to help you better deal with the Cook Islands sun. First, a reef-safe sunscreen list that will keep your skin and the amazing corals of the islands safe, and second, a list of the best sunscreen for kids.

Sunrise and Sunset During December

December has daylight hours lasting about 13 hours a day in the Cook Islands.

• Sunrise: 5.48 am at the beginning of December and 6.00 am at the end of December
• Sunset: 7.08 pm at the beginning of December and 7.24 pm at the end of December.

© CookIslandsPocketGuide.com

Rainfall in December

The wet season is in full swing in December with higher rainfall rates than what’s experienced in the dry season. However, the average days of rainfall are still quite low at around 11 days of December typically experiencing rain. This means that showers are incredibly short but more regular. It is not uncommon on some of the Cook Islands in December to see torrential rain come for literally only 15 minutes.

The Cook Islands receives an average of 229 mm / 9″ of rainfall in the month of December, with around 11 days out of December experiencing rain.

Average Rainfall Across the Cook Islands

• Rarotonga – The average rainfall in December is 229 mm / 9″
• Aitutaki – The average rainfall in December is 232 mm / 9.1″
• Mangaia – The average rainfall in December is 180 mm / 7.1″
• Mitiaro – The average rainfall in December is 189 mm / 7.4″
• Manihiki (North) – The average rainfall in December is 301 mm / 11.9″
• Penrhyn (North) – The average rainfall in December is 242 mm / 9.5″.

© Pixabay

Tropical Storms in December

The South Pacific cyclone season starts in November and ends in April, making December a month with a higher risk of tropical storms.

Historically, the Cook Islands was affected by a tropical cyclone in December 1831, 1842, 1848, 1883, 1925, 1930, 1940, 1943, 1962 and 1967. In more recent history, Cyclone Trina (2001) affected Mangaia in early December, causing flooding and damage to the agricultural sector. Cyclone Val (1991) narrowly missed the Cook Islands in December, causing gale-force winds and damage to crops.

If you want to completely avoid the risk of cyclones in the Cook Islands, it’s best to travel in the dry season. For those planning to travel during December, it’s still a good idea to be aware of what to do in a cyclone by following our guide, Cyclone Safety in the Cook Islands.

© Taniera - Cook Islands Tourism

Best Places to Visit in the Cook Islands in December

Celebrating Christmas is serious stuff for Cook Islanders, so visiting more populated areas, like Rarotonga, can be a fun experience during this time of the year. On the other hand, Rarotonga is often at its busiest over the Christmas period, so if you’re looking for tropical tranquillity, head to one of the outer islands.

Rarotonga – Rarotonga is the most popular island to visit in the Cook Islands and more so in December with both locals visiting family and internationals seeking a tropical Christmas. If you enjoy the “buzz” of this time of year combined with a stunning stay in a resort or eco-accommodation, then Rarotonga is worth considering. Find out more about what Rarotonga is all about in the 50 Best Things to Do on Rarotonga.

Mangaia – Swap the buzz of Rarotonga for this hidden gem of an island; an eco-lovers paradise thanks to its amazing deep caves, coral cliffs and historic maraes, burial chambres and churches. Mangaia is a true South Seas experience that makes an exceptional December destination. What’s more, it’s one of the islands with the least rainfall in December. See what Mangaia is all about in the 15 Best Things to Do in Mangaia.

© CookIslandsPocketGuide.com

December Packing List for Rarotonga and the Cook Islands

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

• High-factor sunscreen (that’s reef-safe and water-resistant)
• Insect repellent
• Light rain jacket
• Light clothing layer (cotton or linen preferably so it is super light)
• Light long-sleeved tops (to cover from sun and mosquitoes)
• Light pants/trousers (to cover the knees when appropriate – church service or to protect from mosquitoes, for example)
• Sunhat
• Sunglasses
• Swimwear
• Closed walking shoes
• Flip-flops/jandals/sandals
• Sarong (pāreu – available on Rarotonga if you don’t have your own)
• A Christmas gift for the family you are staying with if doing a homestay on one of the outer islands, for example.

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