There is no modern record of snow ever falling in Puerto Rico. The lowest temperature on record for Puerto Rico is 39 degrees Fahrenheit, which is too warm for precipitation to fall as snow. Puerto Rico does have a rainy season that lasts from April to November each year.
Puerto Rico is in the tropical climactic zone. Temperatures average 80 degrees Fahrenheit in low elevations and 70 degrees Fahrenheit in mountainous regions. Winter and summer months in Puerto Rico do not vary greatly in temperature, averaging a 6-degree difference. The warm tropical waters of the Atlantic Ocean offset colder air that moves in from the north and northwest.