The 1989–90 South Pacific cyclone season was a below-average season with only five tropical cyclones occurring within the South Pacific to the east of 160°E.[A 1] The season officially ran from November 1, 1989, to April 30, 1990 with the first disturbance of the season forming on November 8 and the last disturbance dissipating on March 19.[A 2] This is the period of the year when most tropical cyclones form within the South Pacific Ocean.
During the season at least 15 people were killed from tropical disturbances whilst overall damage was estimated at &10000000196000000000000$196 million
(1990 USD) of damages to crops and vegetation. As a result of the impacts caused by Ofa and Peni, the names were retired from the tropical cyclone naming lists.
Within the South Pacific, tropical cyclones were monitored by the Tropical Cyclone Warning Centers (TCWC) in Nadi, Fiji, and in Wellington, New Zealand. Whilst tropical cyclones that moved to the west of 160°E were monitored as a part of the Australian region by the Australian Bureau of Meteorology. Both the United States Joint Typhoon Warning Center (JTWC) and the Naval Western Oceanography Center (NWOC) issued unofficial warnings within the southern Pacific. The JTWC issued warnings between 160°E and the 180° meridian whilst the NWOC issued warnings for tropical cyclones forming between the 180° meridian and the coasts of the Americas. Both warning centres designated tropical cyclones with a number and a P suffix with numbers assigned in order to tropical cyclones developing within the whole of the Southern Hemisphere. TCWC Nadi and TCWC Wellington both use the Australian Tropical Cyclone Intensity Scale, and measure windspeeds over a period of ten minutes, while the JTWC and the NWOC measured sustained winds over a period of one minute and use the Saffir–Simpson Hurricane Scale.
On December 19, the remnants of Tropical Cyclone Felicity, moved into the basin with 10-minute sustained windspeeds of 75 km/h (45 mph), which would have made it a category 1 tropical cyclone on the Australian tropical cyclone intensity scale.
However because it did have the "classical characteristics of a tropical cyclone", it was treated as a tropical depression by the Brisbane and Nadi Tropical Cyclone Warning Centres. Over the next couple of days, in response to an upper level trough of low pressure weakening, the depression slowly weakened further, while accelerating to towards the southeast. Felicity was then absorbed by a short-wave trough of low pressure to the north of New Zealand during December 22.
to the west of Tuvalu. Over the next couple of days, the depression moved towards the southeast before recurving towards the southwest, as it started to affect the Fijian Islands on March 19. Over the next couple of days the depression moved towards the south before it recurved again
Rae battered parts of Fiji and Tonga with high seas heavy rain and gale force winds, with 3 deaths and minor damage to crops and vegetation reported in Fiji.
The following weak depressions were also monitored by TCWC Nadi, however these systems were either short lived or did not develop significantly. Between November 8–10 and December 14–17, TCWC Nadi monitored 2 depressions that had developed near the Southern Cook Islands and the Samoan Islands. Between January 20–25, a tropical depression occurred within the monsoon trough over the Coral Sea and caused widespread gale force winds in New Caledonia as it moved south-eastwards. Between February 6–9, TCWC Nadi monitored a tropical depression that developed near the Samoan Islands, and moved towards Niue. On March 15, the precursor shallow tropical depression to Cyclone Ivor developed within the South Pacific convergence zone, about 390 km (240 mi)
to the northeast of Port Villa in Vanuatu. During that day, the low moved towards the southwest and moved into the Australian region where it developed into Tropical Cyclone Ivor during March 16.
This table lists all the storms that developed in the South Pacific basin during the 1989–90 season. It includes their intensity on the Australian Tropical cyclone intensity scale, duration, name, areas affected, deaths, and damages.
↑ 2.02.12.22.32.4RSMC Nadi — Tropical Cyclone Centre, TCWC Brisbane, TCWC Wellington (May 22, 2009). TCWC Wellington Best Track Data 1967–2006. Fiji Meteorological Service, Meteorological Service of New Zealand Limited, Australian Bureau of Meteorology. International Best Track Archive for Climate Stewardship.