irma was the first major hurricane to develop in the eastern atlantic since hurricane julia in 2010. the storm developed on august 30, 2017 near the cape verde islands. on september 5, 2017, the storm became a category 5 hurricane. it had maximum sustained winds of 180 miles per hour since hurricane wilma in twelve years earlier. as it hit landfall, irma went down to a category 2 hurricane. irma was the easternmost category 5 hurricane on record in the atlantic ocean.