After the depression had crossed the International Dateline early on December 25, atmospheric convection surrounding 04F increased and the system became better organized. At this time vertical wind shear over the system rapidly decreased, while the systems outflow significantly improved. As a result, the United States Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert on the system, before they initiated advisories on the system and designated it as Tropical Cyclone 06P. Later that day at 21:00 UTC (08:00 December 26 SIT) the FMS reported that the depression had become a Category 1 tropical cyclone, on the Australian tropical cyclone intensity scale and named it Zoe. At this time the system was located about to the northwest of the Fijian Dependency; Rotuma and moving westwards at about .