The best months to visit Cook Islands are June and August. See monthly temperatures, rainfall and rain days (1991–2020 averages) to plan your trip.
Average daytime high and monthly rainfall in Cook Islands: January 24°C / 216mm; February 25°C / 182mm; March 26°C / 189mm; April 25°C / 153mm; May 24°C / 135mm; June 22°C / 65mm; July 22°C / 100mm; August 21°C / 70mm; September 22°C / 73mm; October 22°C / 86mm; November 22°C / 110mm; December 24°C / 189mm.