Cook Islands · Month comparison
May vs September
May ranks #1 overall vs September at #4. Dry season opens — the crowd-to-value sweet spot before New Zealand winter school holidays.
May
#1 of 12 months
Best match
Dry season opens — the crowd-to-value sweet spot before New Zealand winter school holidays.
- ↑85mm of rain is genuinely manageable — most days are dry and clear
- ↑Prices still below the June–August premium before school holidays hit
September
#4 of 12 months
Best match
Dry season continues — school holidays end, prices soften slightly, conditions remain excellent.
- ↑School holiday crowds thin after the first week — far easier to book Aitutaki day trips
- ↑Prices beginning to ease from July–August peak while weather remains exceptional
| Factor | May | September |
|---|---|---|
| Weather score | 8 | 9 |
| Value score | 7 | 6 |
| Crowd score | 7 | 6 |
| Events score | 5 | 5 |
| Atmosphere | 8 | 8 |
| Avg high temp | 24°C | 23°C |
| Monthly rain | 85mm | 70mm |
| Daily sunshine | 7hrs | 7.5hrs |
May trade-offs
- ↓Evenings noticeably cooler than summer — pack a layer for open-air dinners
- ↓Some activities (lagoon cruises, sailing) operate reduced schedules before the main season
- ↓Less vibrant green in the interior as dry season bites
September trade-offs
- ↓Still 70mm of rainfall — occasional brief showers occur in the evenings
- ↓Some operators begin reduced scheduling ahead of the wet season return
- ↓Water still cool at 17°C low — not the warmest swimming conditions
Scores compare months within Cook Islands. Climate data: Open Meteo ERA5 30-year normals (1991–2020). Methodology →