Hurricane Irma was an extremely powerful and catastrophic Cape Verde type hurricane, the strongest observed in the Atlantic since Wilma in 2005 in terms of maximum sustained winds. It was the first Category Five hurricane to strike the Leeward Islands, followed by Hurricane Maria only two weeks later. It was also the most intense Atlantic hurricane to strike the United States since Katrina in 2005, and the first major hurricane to make landfall in Florida since Wilma in 2005. The ninth named storm, fourth hurricane, and second major hurricane of the 2017 Atlantic hurricane season, Irma caused widespread and catastrophic damage throughout its long lifetime, particularly in parts of the northeastern Caribbean and the Florida Keys.

On September 6, 2017 Irma reached its peak intensity with 185 mph winds and a minimum pressure of 914 hPa, making it the second most intense tropical cyclone worldwide so far in 2017, behind only Hurricane Maria, and the strongest worldwide in 2017 in terms of wind speed. Irma dropped back to Category 3 by the time it made a second Florida landfall on Marco Island. Irma weakened to a Category Two hurricane later that day, the first time it weakened below major hurricane status in over a week, and eventually dissipated off the coast of New England.

The storm caused catastrophic damage in Barbuda, Saint Barthélemy, Saint Martin, Anguilla, and the Virgin Islands as a Category Five hurricane and extensive damage from wind and flooding in parts of Florida, and Georgia. In Charleston, South Carolina the third highest storm surge on record was recorded, reaching a height of approximately 10 ft. Light damage occurred in other areas, including Tennessee and hundreds of thousands reported losing power in Upstate South Carolina and North Carolina due to Irma.