Weather
Seasonal Climate
Temperatures in Guaynabo average 78-83 degrees Fahrenheit year-round. December-April are the coolest months. Sweaters are necessary in the mountains during winter. In the hottest months, July-September, temperatures often top 90 degrees Fahrenheit. About 59 inches of rain falls annually on the island, most of it during hurricane season (June-November). But rain can fall in brief torrents year-round.
Today's Weather