Forming out of an upper-level low pressure system on November 29 near the island of Rarotonga, or roughly 1,470 mi (2,365 km) southeast of Fiji, Trina remained practically stationary as it meandered in the same general area for over a week.

[2] However, the system later entered an area unfavorable to tropical cyclogenesis, consisting of increasing shear and marginally warm sea surface temperatures, estimated between 26 and 27 °C (79 and 81 °F).

Drifting westward, convection managed to increase despite unfavorable conditions, as the low passed roughly 45 km (30 mi) southwest of Rarotonga on November 30.

[1] The JTWC only classified Trina as a tropical storm for 12 hours before downgrading the system and issuing their final advisory early on December 1.

[6] Owing to the slow movement of the storm, heavy rains associated with Trina fell on Mangaia for nearly eight days, resulting in widespread flooding.

Following an assessment made by the Cook Islands National Disaster Management Council, it was determined that US$52,000 was needed to repair losses from Trina.

International assistance from the United Nations was eventually requested on December 12, allowing for relief funds from several agencies to be delivered to the area.

[12] A total of US$24,140 was committed in relief funds by New Zealand, Norway and the United Nations to assist the Cook Islands in recovering from the storm.

[14] In the months following Cyclone Trina, debris removal and cleanup was relatively slow, delaying efforts to replant crops lost in the floods.