1989–90 South Pacific cyclone season

Tropical depression (Australian scale)
Tropical depression (SSHWS)
Duration	December 19 – December 22
Peak intensity	75 km/h (45 mph) (10-min)  990 hPa (mbar)

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 scale.[2] However, because it did not have the "classical characteristics of a tropical cyclone", it was treated as a tropical depression by the BoM and the FMS.[3][4] 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.[3] Felicity was absorbed by a short-wave trough of low pressure to the north of New Zealand before it was last noted during December 22.[3][2]

Tropical depression (Australian scale)
Duration	January 20 – January 25
Peak intensity	65 km/h (40 mph) (10-min)

On January 20, TCWC Nadi started to monitor a shallow area of low pressure that had developed within a trough of low pressure, about 600 mi (965 km) to the Northwest of Noumea in New Caledonia.[5]

The depression was last noted on January 25, as it moved into TCWC Wellington's area of responsibility.[5][6][7]

There were no reports of any damage associated with this depression within New Caledonia, which was largely due to its small and not so intense nature of the system.[5]

Category 4 severe tropical cyclone (Australian scale)
Category 4 tropical cyclone (SSHWS)
Duration	January 27 – February 10
Peak intensity	185 km/h (115 mph) (10-min)  925 hPa (mbar)

On January 27, a shallow tropical depression formed within the South Pacific Convergence Zone, about 430 km (265 mi) to the southeast of Funafuti, Tuvalu.[8] Over the next two days the system developed little and remained slow moving, near the Tuvaluan atoll of Funafuti.[8] During January 30, the depression moved towards the north-east and started to organize, as pressures near the systems center rapidly falling.[8] During the next day the system subsequently started to curve south-eastwards and away from Tuvalu, before the NWOC initiated advisories on the system and designated it as Tropical Cyclone 13P.[9][10] Late on January 31, TCWC Nadi named the tropical depression Ofa, after it had developed into a category 1 tropical cyclone on the Australian scale.[9][2] Over the few days the system moved towards the south-southeast and intensified further. Ofa subsequently passed about 110 km (70 mi) to the west of the Western Samoan Island of Savai'i between 10:00 and 18:00 UTC during February 3.[9] Early the next day as the system started to accelerate towards the south-southeast towards the island nation of Niue, the NWOC estimated that Ofa had peaked with 1-minute sustained wind speeds of 215 km/h (130 mph), which made it equivalent to a category 4 hurricane on the SSHWS.[11] Later that day TCWC Nadi also estimated that the system had peaked with 10-minute sustained wind speeds of 185 km/h (115 mph) as a category 4 severe tropical cyclone,.[2] During February 5, the system passed about 55 km (35 mi) to the west of Niue, as it started to weaken and started to transition into an extratropical cyclone.[7][9] The system completed this transition during February 8, before the remnants were last noted during February 10 after they had performed a small clockwise loop.[7]

Cyclone Ofa affected seven different island nations and caused gales or much stronger winds in six of those countries which resulted in damage ranging from moderate to very severe.[9] Storm tide from the cyclone which is the combined effect of storm surge and high tide caused havoc in several countries and was the major cause of destruction.[9] Overall the system killed at least eight people while it was estimated that the overall damage would amount to over US$180 million with damage totals of at least US$150 million and US$30 million in Western and American Samoa.[9]

Category 1 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration	January 31 – February 1
Peak intensity	85 km/h (50 mph) (10-min)  987 hPa (mbar)

Late on January 30, TCWC Nadi started to issue warnings on a tropical depression, that was intensifying as it moved southeastwards and approached 160°E and the South Pacific tropical cyclone basin.[12] The system subsequently moved into the basin early the next day and was named Nancy by TCWC Nadi, after it had become a category 1 tropical cyclone.[12][13] During that day the system re-curved and started to move towards the south-southwest, as it was steered around the southern extension of an upper level trough of low pressure.[12] The system subsequently moved out of the basin during February 1, as it intensified into a category 2 tropical cyclone.[2][13] While the system was in the basin the JTWC estimated that Nancy had peak 1-minute sustained winds of 215 km/h (130 mph), which made it equivalent to a category 1 hurricane on the SSHWS.[14] The system subsequently re-entered the basin as an extratropical cyclone on February 6, before it dissipated to the west of New Zealand on February 8.[13] There was no damage associated with Nancy while it was in the basin, however it later caused 5 deaths, when it affected the Australian states of Queensland and New South Wales.[13]

Tropical depression (Australian scale)
Duration	February 6 – February 9
Peak intensity	65 km/h (40 mph) (10-min)

On February 6, the FMS reported that a depression had developed, within the South Pacific Convergence Zone near the islands of Tuvalu.[15] Over the next few days the system was steered towards the southeast by a north-westerly steering flow on the eastern side of an upper level trough of low pressure.[15] As the depression moved towards the southeast it passed in between Western Samoa and the northern islands of Tonga before it came very close to Niue during February 8.[15] Despite marginal gale-force winds being present in the depressions eastern quadrant, strong north-westerlies prevented the depression, from strengthening into a tropical cyclone.[15] The depression was subsequently last noted during February 9, as it was absorbed into the Westerlies.[15] The only damage that could be attributed to the depression is a number of houses that were destroyed on the Tuvaluan atoll of Vaitupu on February 6, however it is possible that the houses were destroyed by the strong and squally north-westerlies that were prevailing over the northern islands of Tuvalu at that time.[15] As Tuvalu, Western Samoa, American Samoa, Tonga, Niue had all been affected by Cyclone Ofa a few days earlier; any damage would have been difficult to assess.[15]

Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration	March 7 – March 7
Peak intensity	95 km/h (60 mph) (10-min)  985 hPa (mbar)

During March 7, Tropical Cyclone Hilda moved into the basin from the Australian region, as a category 2 tropical cyclone while it was located about 640 km (400 mi) to the northeast of Noumea, New Caledonia.[2][16] During that day, the system passed about 640 km (400 mi) to the south-west of New Caledonia, as it moved south-southwestwards and degenerated into an extratropical depression.[16] Over the next couple of days, the system moved through the Tasman Sea and passed near New Zealand's South Island, before it was absorbed into a high-latitude trough of low pressure.[7]

Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
Duration	March 16 – March 23
Peak intensity	95 km/h (60 mph) (10-min)  985 hPa (mbar)

On March 16, TCWC Nadi started to monitor a shallow tropical depression that had developed within the South Pacific Convergence Zone, about 400 km (250 mi) to the west of the Tuvaluan Islands.[2][17] The system initially moved slowly towards the south — southeast and passed about 95 km (60 mi) to the east of the Fijian Dependency of Rotuma during March 18.[18] Over the next 24 hours the system moved southwards before it turned towards the southwest during March 19, as it approached and started to affect the Fijian Islands.[17] At this time the depression appeared disorganised in satellite imagery, with estimated sustained windspeeds of between 35 to 55 km/h (20 to 35 mph) in a broad area to the north and east of the depression center.[17][19] During the next day the depression passed about 65 km (40 mi) to the west of the Yasawa group of islands as it continued to move towards the southwest.[17]

The following 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.[20][21] 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.[22] 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.[22]