You'll likely spend much of your trip indoors, but if you're planning to venture beyond the casino, looking at local weather trends is a good idea. The hottest months are usually March and April, with an average temperature of 25°C, while the coldest months are January and December, with an average of 24°C. The rainiest months in Manuel Antonio are October, August, July and June, with each month seeing an average of 1054 mm of rainfall.