August is an excellent time to visit the Cook Islands despite the cooler temperatures. You can expect mild, balmy weather, mainly clear, sunny skies with little or no rainfall and cool evenings.
The comfortable mild weather is ideal for a range of outdoor activities, including snorkelling, scuba diving and spotting humpback whales during their migration to the Cook Islands.
How hot is it in the Cook Islands in August?
Daytime temperatures average a high of 25°C (77°F) in the Cook Islands in August, with low heat and humidity, falling to a night-time low of 19°C (66°F).
How sunny is it in the Cook Islands in August?
There are normally six hours of sunshine each day in the Cook Islands in August – that's around 54% of daylight hours.
Sunrise & sunset in August?
Sunrise is around 7:00am with sunset around 6:25pm.
How warm is the sea in the Cook Islands in August?
The average sea temperature in the Cook Islands in August is 24°C (75°F), which is still pleasant for swimming.
Does it rain in the Cook Islands in August?
Monthly rainfall in the Cook Islands in August averages 50mm (2in), distributed across six days on average.
How windy is it in the Cook Islands in August?
August sees an average wind speed of around 22 kilometres per hour (14 mph; 12 knots). The predominant average wind direction in the Cook Islands is from the east.
What to do in the Cook Islands in August?
August offers a good combination of weather for a range of water sports, including swimming, scuba diving and snorkelling.
The mild temperature is also good for hiking and exploring the islands.
August falls in the middle of the whale watching season.
Local holidays?
Constitution Day – 4th/5th Aug.
As August falls within the winter peak holiday season it’s best to book accommodation and flights early.
![]() |
High Temp: 25°C (77°F) |
![]() |
Low Temp: 19°C (66°F) |
![]() |
Sunshine: 6 hours per day |
11
![]() |
Daylight: 11 hours per day |
![]() |
Wet Days: 6 days with some rain |
![]() |
Rainfall: 50mm (2in) per month |
![]() |
Comfort Level: Low heat & 80% humidity |
8
![]() |
UV Index: High |
![]() |
Wind speed: 22 km/h (14 mph; 12 knots) |
![]() |
Sea Temp: 24°C (75°F) |
Avarua, Rarotonga, Cook Islands |
The best time of year to visit the Cook Islands is during the winter dry season from June through September.
For warmer weather visit in April and May, or in October and November when you can expect higher temperatures but also the probability of more rain showers.
› Cook Islands weather overview…
Note: Meteorological data for the Cook Islands is based on weather statistics gathered for the 30-year period 1991 to 2020, and is sourced from the Cook Islands Meteorological Service at the closest weather station, Rarotonga International Airport (RAR), located less than 3km (2mi) west of Avarua Harbour. Additional climate data is sourced from the World Meteorological Organization (WMO).
Advice on the best time to visit a particular destination is based on average local weather statistics, when the weather conditions are generally better than at other times of the year. We consider high and low temperatures, risk of rain (and thunderstorms, etc.), amount of sunshine and sea temperature. For general outdoor activities we favour clear, rainless days with a temperature range between 18°C (64°F) and 27°C (80°F); and for hot-weather activities we favour clear, rainless days with a temperature range between 24°C (75°F) and 32°C (89°F). Often, the best times to visit correspond to high season and therefore involve higher prices.
Latest update: Cook Islands weather in August: 24 October, 2023
Disclaimer: The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data and conditions at any given location and time are unpredictable and variable. We assume no responsibility and can not be held legally responsible for any decisions made on the basis of the information presented on this site.
Advertising