The 2017 season produced 17 named storms, of which 10 became hurricanes including six of which intensified into major hurricanes (Category 3, 4 or 5). Of those six, Harvey and Irma, became the first major hurricanes to make landfall on the continental United States in 12 years; a third hurricane, Nate, did so as well. September was both the most active month in the season and the most active month for Atlantic hurricanes ever recorded. Four long-lived major hurricanes—Irma, Jose, Lee and Maria—moved through the Atlantic Basin, as did the short-lived Hurricane Katia. Overall, more accumulated cyclone energy was generated during September 2017 than during the entire 2016 season. In April 2018, the World Meteorological Organization retired the names "Harvey", "Irma", "Maria", and "Nate" from its rotating naming lists due to the number of deaths and amount of damage they caused, and they will not be used again for another Atlantic hurricane.