The hottest month in The Cook Islands is February when the average maximum temperature is 29°, average temperature is 27° and average minimum temperature is 24°.
The coolest month in The Cook Islands is August when the average maximum temperature is 25°, average temperature is 22° and average minimum temperature is 20°.
The longest days in The Cook Islands are in December, with an average of 13.4 hours of daylight per day. June has the shortest days with an average of 10.8 hours of daylight per day.
The sunniest days in The Cook Islands are in December which has the most hours of sunshine per day with an average of 7.5 hours of sunshine per day, making it a quite sunny month with some cloud cover. July has the least sunshine with an average of 2.5 hours of sunshine per day, making it not a particularly sunny month.
The ultraviolet index is the highest in January when it reaches 15.7 and lowest in June when it reaches 6.
An ultraviolet index reading above 11 indicates an extreme risk of harm from unprotected sun exposure. Unprotected skin risks burning in less than 10 minutes. Take all precautions because unprotected skin and eyes can burn in minutes. Tanning will be safest before 10am and after 4pm but only with a good application of sun screen. For those with sensitive skin stay in the shade and wear protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 30+ sunscreen every 2 hours, even on cloudy days. Watch out for relections from water that may increase ultraviolet exposure.
The warmest sea water temperatures in The Cook Islands are found in March when they peak at 28° and lowest in August when they dip to 24°.
The sea is best for swimming between December and May when the temperature is above 26° which is very warm and ideal for relaxing and swimming for the whole day.
The wettest month in The Cook Islands is February with 9.6cm of rain and January has the most days of rain with 14.8 days with some rain, a slightly wet time to visit the beach.
The driest month in The Cook Islands is April with 1.4cm of rain and October has the fewest days of rain with 10.8 days with some rain, a slightly wet time to visit the beach.
The most humid month in The Cook Islands is February with a dew point (an indicator of humidity) of 25° which is very uncomfortable and fairly oppressive unless you are on a beach. At night you would most likely require airconditioning.
The least humid month in The Cook Islands is August with a dew point of 20° which is somewhat uncomfortable for most people in cities but fine on a beach.
The most windy month in The Cook Islands is September when the average maximum windspeed is 26kmh and the average wind speed is 15kmh.
The least windy month in The Cook Islands is April when the average maximum windspeed is 23kmh and the average wind speed is 12kmh.