June 21st marks the first day of summer with an average high temperature of 88° F. At the peak of summer, the average high is 89° F (32° C). Luckily Marathon doesn't have any super-highways or urban sprawl to radiate the sun's heat and our islands are surrounded by cooling ocean waters.

Sun-wise Floridians from the mainland flock to Marathon on steamy weekends to take advantage of the cooler air. The water temperature might be in the mid-80s (30° C), but the sea is nevertheless refreshing for swimming, snorkeling or diving. Afternoon thunderstorms are common in the summer months, but the rain rarely sticks around long enough to spoil an entire day.

You may be wondering about the Atlantic hurricane season, which can affect Florida Keys tourism in the Atlantic and Gulf coasts of the United States. The official hurricane season begins June 1st and ends on November 30th. Traditionally, the highest potential for storms is between August 15th and October 15th. We offer a hurricane clause to protect our guests from storms so please inquire within our call center.