The 2004–05 South Pacific cyclone season was an above-average season in which tropical cyclones formed within the South Pacific Ocean to the east of 160°E. The season officially ran from November 1, 2004 to April 30, 2005, however a tropical cyclone could form at any time between July 1, 2004 and June 30, 2005 and would count towards the season total. The season got off to an early start, when Tropical Depression 01F developed near the Solomon Islands on October 28, three days before the official start of the season. The final disturbance of the season dissipated as the season was drawing to a close on May 1. The season was above-average in terms of activity, with 9 tropical cyclones and 5 severe tropical cyclones forming during the season. The season featured Cyclone Percy, the most intense of the season in terms of pressure.

Severe Tropical Cyclone Percy was an extremely powerful tropical cyclone which was the third and last Category 5 cyclone to form in the 2004–05 South Pacific cyclone season. The seventh named storm and the fourth and final severe tropical cyclone to form during the 2004–05 South Pacific cyclone season. Percy originated as a tropical disturbance on February 23. Over the course of the next few days, the system organized while moving east-southeastward, before intensifying into a Category 1 tropical cyclone on the Australian region scale on February 26. The system quickly intensified, reaching Category 4 status later that day. On the next day, Percy was steered southward by a blocking ridge of high pressure, while stretched out the structure of the storm into an elliptical shape, weakening it back to Category 3 status. Afterward, the storm rapidly reintensified, reaching its peak intensity as a Category 5 tropical cyclone on March 2. Afterward, Percy encountered increasing wind shear and weakened once again, turning southeastward on the next day. On March 5, Percy transitioned into an extratropical storm, before dissipating soon afterward.