Hurricane Olivia was a Category 4 hurricane that impacted Hawaii as a weakening tropical storm in mid-September 2018, causing severe flooding and wind damage. Olivia was the first tropical cyclone to make landfall on Maui and Lanai in recorded history. It was the fifteenth named storm, ninth hurricane, and sixth major hurricane of the 2018 Pacific hurricane season.

The 2018 Pacific hurricane season was one of the most active Pacific hurricane seasons on record, producing the highest accumulated cyclone energy value on record in the basin. The season had the fourth-highest number of named storms – 23, tied with 1982. The season also featured eight landfalls, six of which occurred in Mexico. The season officially began on May 15 in the Eastern Pacific, and on June 1 in the Central Pacific; they both ended on November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. However, tropical cyclone formation is possible at any time of the year, as illustrated when the first tropical depression formed on May 10, five days prior to the official start of the season.