Rarotonga (Cook Islands) in September
In September, Rarotonga (Cook Islands) averages 22°C (71°F) during the day and 20°C (69°F) at night, with frequent rain — about 21 days of the month see precipitation (73 mm total).
ShoulderConditions are comfortable for sightseeing without being sweltering. Expect daily rain or showers, often in heavy bursts.
September offers comfortable temperatures in Rarotonga (Cook Islands), with some rain to plan around.
How September compares to the rest of the year in Rarotonga (Cook Islands)
September is one of the coolest months in Rarotonga (Cook Islands) (11th of 12) and one of the driest months (12th of 12). Daytime temperature runs 2°C below the annual average (23°C). September runs roughly the same as August (21°C) and stays flat into October.
September sunrise & sunset in Rarotonga (Cook Islands)
Times shown for Rarotonga (Cook Islands) local time (Pacific/Rarotonga), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in Rarotonga (Cook Islands) — September
Golden-hour and blue-hour windows for the 15th of September, in Rarotonga (Cook Islands)'s local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Rarotonga (Cook Islands) in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and Rarotonga (Cook Islands)'s popularity.
Crowds & pricing — September in Rarotonga (Cook Islands)
Rarotonga (Cook Islands) is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.
Why this tier: comfortable tourism weather
Sun & mosquito risk — September in Rarotonga (Cook Islands)
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Sea temperature in Rarotonga (Cook Islands) — September
Across the year Rarotonga (Cook Islands)'s sea swings from 24.1°C (October) to 28.3°C (March) — September sits at 24.2°C.
Rarotonga (Cook Islands) in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 25°C / 76°F | 23°C / 74°F | 237 mm | 27 | — |
| February | 25°C / 77°F | 24°C / 74°F | 182 mm | 24 | — |
| March | 25°C / 77°F | 24°C / 74°F | 253 mm | 28 | — |
| April | 24°C / 76°F | 23°C / 73°F | 146 mm | 22 | — |
| May | 23°C / 74°F | 22°C / 72°F | 163 mm | 24 | — |
| June | 22°C / 72°F | 21°C / 70°F | 92 mm | 23 | — |
| July | 22°C / 71°F | 20°C / 69°F | 111 mm | 22 | — |
| August | 21°C / 70°F | 20°C / 68°F | 92 mm | 22 | — |
| September | 22°C / 71°F | 20°C / 69°F | 73 mm | 21 | — |
| October | 22°C / 71°F | 21°C / 69°F | 101 mm | 22 | — |
| November | 23°C / 73°F | 22°C / 71°F | 97 mm | 22 | — |
| December | 24°C / 75°F | 22°C / 72°F | 186 mm | 22 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for Rarotonga (Cook Islands) in September →
Frequently asked questions
How hot is Rarotonga (Cook Islands) in September?
In September, Rarotonga (Cook Islands) averages a high of 22°C (71°F) and a low of 20°C (69°F) — generally mild and pleasant.
Does it rain a lot in Rarotonga (Cook Islands) in September?
September is quite rainy in Rarotonga (Cook Islands), with about 21 rainy days on average.
Is September a good time to visit Rarotonga (Cook Islands)?
September is mild and pleasant but on the rainy side. It suits travelers who are comfortable with mild and pleasant weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Rarotonga (Cook Islands) in September?
Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full September packing list for Rarotonga (Cook Islands) for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.