If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Puntarenas: The hottest months are usually March and February with an average temp of 81°F, while the coldest months are January and December with an average of 79°F. The rainiest months in Puntarenas are October, August, June, and September, with each month seeing an average of 19 inches of rainfall.