Things to Do in Cook Islands in December
December weather, activities, events & insider tips
December Weather in Cook Islands
Is December Right for You?
Advantages
- Peak summer weather with consistent 28°C (82°F) highs - December sits right in the Cook Islands dry season, giving you the most reliable beach weather of the year. The lagoons are typically glassy calm, visibility underwater pushes past 30 m (98 ft), and you'll actually want to be outside all day.
- School holidays mean vibrant local energy without overwhelming crowds - Kiwi families arrive for their summer break, which adds life to the islands without the crush you'd get in European peak seasons. Local events ramp up, restaurants extend hours, and there's a genuine festive atmosphere that feels participatory rather than touristy.
- Whale season overlap in early December - If you arrive in the first two weeks, you might catch the tail end of humpback whale season (typically July through October, but stragglers hang around). December 2026 could give you both prime beach weather AND whale encounters, which is rare timing.
- Mango season peaks with incredible local produce - December marks the height of mango madness across Rarotonga and Aitutaki. Roadside stalls sell them for next to nothing, restaurants feature them in everything, and you'll taste varieties that never make it to export markets. The passionfruit are exceptional too.
Considerations
- Premium pricing across accommodations and flights - December commands the highest rates of the year, often 40-60% above shoulder season prices. Beachfront properties on Rarotonga book out 6-8 months ahead, and last-minute deals simply don't exist. If budget flexibility matters, you'll find better value in May or November.
- Tropical storm risk increases as the season progresses - While December sits early in cyclone season (November through April), the risk isn't zero. Late December 2026 could see developing systems, and even storms that don't hit directly can bring 2-3 days of heavy rain and rough seas that cancel boat trips and diving.
- Limited availability requires rigid planning - The combination of peak demand and the Cook Islands' small scale means you can't just wing it. Popular activities like Aitutaki lagoon cruises, specific rental cars, and better restaurant tables need advance booking. Spontaneity takes a hit when everything requires reservations.
Best Activities in December
Rarotonga Lagoon Snorkeling and Swimming
December delivers the clearest lagoon conditions of the year - water temps sit around 27°C (81°F), visibility often exceeds 25 m (82 ft), and the calm seas mean even nervous swimmers feel comfortable. The inner lagoon stays protected by the reef, creating a natural pool that's perfect for families. Morning sessions (7-10am) offer the best light for underwater photography before the UV gets intense. The marine life is particularly active right now, with juvenile fish sheltering in the coral before summer storms arrive.
Aitutaki Lagoon Day Trips
Aitutaki's lagoon is legitimately one of the most stunning in the Pacific, and December weather makes it accessible almost daily. The trademark turquoise water, tiny motus (islets), and shallow sandbars are at their photogenic best under consistent sunshine. Most tours include snorkeling stops, a motu picnic, and plenty of time wading in knee-deep water that looks Photoshopped. The 45-minute flight from Rarotonga is an activity itself - you'll see the reef systems from above. December's calm conditions mean fewer cancelled tours compared to cyclone season proper.
Cross-Island Trek on Rarotonga
The Cross-Island Track cuts through Rarotonga's interior jungle, climbing to 413 m (1,355 ft) before descending to the opposite coast. December's humidity makes this a proper workout - you'll be drenched in sweat - but the vegetation is lush, waterfalls are flowing from recent rains, and the forest canopy provides shade. Start at 7am to finish before midday heat. The track takes 3-4 hours one-way, and most people arrange a pickup on the opposite side rather than doubling back. Views from Te Rua Manga (The Needle) are worth the climb, though the final scramble requires decent fitness.
Traditional Island Night Cultural Shows
December's visitor numbers mean the weekly island nights run at full energy with 20-30 minute dance performances, fire dancing, and traditional drumming. These aren't manufactured tourist shows - the performers are locals who grew up with these traditions, and the skill level is genuinely impressive. The buffet dinners feature umu-cooked food (earth oven), including whole fish, taro, and rukau (taro leaves in coconut cream). It's the best introduction to Cook Islands Maori culture, and the festive December atmosphere adds extra energy to the performances.
Scooter Circumnavigation of Rarotonga
The 32 km (20 mile) coastal road around Rarotonga makes for a perfect scooter day trip - you can complete the loop in 45 minutes without stops, but the point is stopping everywhere. December's weather is ideal for this: minimal rain risk, warm but not scorching, and the coastal breeze keeps you comfortable. Stop at fruit stalls, swim at different beaches, visit the Punanga Nui Market (Saturday mornings are best), and pull over for roadside views. The road is flat, well-maintained, and traffic is light. You'll see more of the island's character in one scooter day than a week at a resort.
Lagoon Kayaking and Stand-Up Paddleboarding
December's calm lagoon conditions make this the premium month for paddling. The water is warm enough that falling in is refreshing rather than shocking, and the morning glass-offs (flat, mirror-like water) are frequent. Kayaking lets you access reef areas boats can't reach, and you'll spot fish, rays, and occasionally turtles in the shallows. SUP works better in the protected lagoon sections - the outer reef areas get choppy even in good weather. Sunset paddles are particularly beautiful in December when the sun sets around 8pm, giving you long evening light.
December Events & Festivals
Punanga Nui Market Saturday Sessions
While this market runs year-round, December sessions are exceptional because of the mango glut and festive atmosphere. Local vendors sell fresh produce, handmade crafts, pareus (sarongs), and cooked food. The quality of tropical fruit right now is absurd - mangoes, pawpaw, passionfruit, and starfruit at prices that feel like errors. Live music starts around 9am, and the energy peaks between 9-11am. This is where locals actually shop, not a tourist fabrication, which gives it genuine character.
Christmas and New Year Celebrations
The Cook Islands do Christmas with serious enthusiasm - church services feature incredible harmonized singing (the Cook Islands Maori are known for their voices), families gather for massive feasts, and there's a genuine community feel. Many restaurants and tours close December 25-26, so plan accordingly. New Year's Eve brings beach parties, resort events, and fireworks visible from most of Rarotonga's coast. It's festive without being chaotic, and the warm weather makes outdoor celebrations comfortable.