The name Ilsa has been used for one tropical cyclone in the Atlantic Ocean, three tropical cyclones in the Eastern Pacific Ocean, and two in the Australian region. It was used in the Atlantic before the formal naming system was instituted, and in the Pacific with the old four-year lists.
Atlantic:
Pacific:
Ilsa has been used for at least two tropical cyclones in the Southern Hemisphere:
References
Tropical Storm Ilsa Wikipedia(Text) CC BY-SA