Tropical Storm Irma was the ninth tropical cyclone as well as the ninth named storm in the 1978 Atlantic hurricane season. Irma developed from a subtropical system that was located about 500 miles (805 km) south of to the Azores. The system gained more tropical characteristics and was classified as Tropical Depression Nine beginning on October 2. The storm strengthened into a tropical storm before it tracked in between the western and central sections of the Azores.