Het weer in Avarua (Rarotonga) in september

September is the turn into Rarotonga's warmer half - more sun than June, longer days - and a busy month for the island. Avarua is the practical half of that: the capital sits between the two northern harbours and holds the banks, the shops and the businesses, which is why most trips pass through it whatever else they do. The fixture worth planning around is the Saturday morning market, for local food and fresh produce, with island nights for the performances. Our row's 30.7 kph wind is the equinox breeze that shapes the rest of the island in this month. The record: 26.5C days that feel like 27C, 20.2C nights, 10.1 precipitation days carrying 83mm, 9.9 hours of sun and a 23.9C sea.

Regulars are specific this counts as a genuine mixed bag, clear sunny stretches alongside real cloudy, showery days, cool nights capable of needing a warmer layer even as one visitor found daytime conditions as warm as a summer day back home. Our row backs that mild, genuinely wet read, 26.8C over 20.4C nights feeling 19C, with 73.4mm of rain across 9.6 days and a real 30.8 kph wind. Regulars are consistent the island's own north side, running through Avarua itself, is favored locally for running warmer than other parts, with nearby Aitutaki typically a degree or two warmer still thanks to its shallower, faster-warming lagoon. The sea sits at a warm 25.3C. The record: 8.8 hours of sun, humidity 74 percent and AQI 37.

October is late spring here and regulars sell it on quiet rather than certainty: the shoulder season, the island noticeably emptier, and weather they will not forecast - a week of rain or a week of sun, because this is the end of the dry season and the South Pacific rains in its dry season too. Our 115.9mm across 9.2 days says they are right to hedge. Days reach 26.6C and feel like 28C; nights drop past 20.5C and the board's advice is a jumper, which surprises people who packed for the tropics. A 31.8 kph wind runs across the island all month. The sea is 24.2C. The record: humidity 76 percent, 10 hours of sun and AQI 47.

Forum posters describe May as early winter in the Cook Islands, with the islands turning the corner away from summer's heat and humidity by the end of April while still remaining a very pleasant month overall. Posters report a real mixed bag of conditions - some rainy days alongside some genuinely hot ones, plus noticeably windy stretches from the southeast on occasion - with the lagoon water staying pleasantly warm throughout. Posters recommend the island's west coast over the south if wind becomes an issue during a stay. Posters generally describe May through October as the drier, cooler half of the year compared to the warmer December-through-April stretch, positioning May as a comfortable transitional month around Avarua.

Avarua's forum calls November warm and increasingly humid as the South Pacific rainy season approaches, with showers more frequent than October but nights still comfortable enough to sleep without air conditioning. If you're timing a visit around it, the Vaka Eiva outrigger canoe festival is based right at Avarua harbour and typically runs in November.