Planning for the weather is a good way to make your trip to Nosara relaxing and enjoyable, especially when you’re splurging. The hottest months are usually March and April with an average temp of 81°F, while the coldest months are December and January with an average of 79°F. The rainiest months in Nosara are October, September, June, and August, with each month seeing an average of 15 inches of rainfall.