Feature article

Tropical cyclone update

The tropical cyclone outlook for the current moderate El Niño season (2002/2003) forecasts an eastward spread in cyclone occurrence, with more cyclones than normal expected east of the dateline, and somewhat fewer than normal in the west. So far, the observed pattern of cyclone occurrence has matched well with the forecast pattern.

This tropical cyclone season (2002/2003) (see Figure 1 below) has been more active than past few seasons with ‘Yolande’, which did not affect any countries and ‘Zoe’ affecting Solomon Islands, Vanuatu in December 2002. January 2003 was more active with ‘Ami’ causing havoc in Fiji and Tonga, ‘Beni’ affecting Vanuatu and New Caledonia and ‘Cilla’ affecting Tonga.

‘Yolanda’ developed over southern Tuvalu on 1st December 2002 and then tracked south, passing east of Fiji on the 4th, then southeast over southern Tonga on the 5th. Maximum sustained winds reached 74 km/hr. Fortunately, no damage was caused by this event.

‘Zoe’ formed on Christmas eve (24th December 2002) from a tropical depression near Tuvalu and Fiji’s Rotuma Island, intensifying to tropical cyclone intensity as it tracked west on the 26th. The system became very intense (Category 5, i.e. the strongest in hurricane definitions) over the Santa Cruz Islands of Tikopia and Anuta in the Solomon Islands from the 28th through to the 30th, generating high seas, with estimated maximum sustained wind speeds of 287 km/hr, and gusts to 350 km/hr. This event devastated these islands, however there were no casualties.

‘Ami’ developed just southeast of Tuvalu on 12th January 2003 and moved southeast towards Fiji’s northern island of Vanua Levu. From the 13th to the 14th, Ami devastated the northern parts of Fiji and Lau Group (southeast island group of Fiji) as it moved south. Average winds of 200 km/hr with momentary gusts of 230 km/hr were reported. Ami further tracked southwest to pass just southwest of Tonga bringing enormous seas and windespread wind and rain damage to the small island nation. Although Ami was not as strong as Zoe, it caused widespread damage in Fiji as it swept over a much larger area of habitants, killing 14 people. Fiji’s Disaster Management Centre declared northern island of Vanua Levu a natural disaster zone. Fiji and Tonga are still reeling from damages of the tropical cyclone Ami.

‘Beni’ formed from a depression just south of the Solomon Islands on 26th January 2003. The system remained stationary over the Renell Bellona Group (the southern group of the Solomon Islands), where 2000 people took shelter in caves. Beni initially moved west then southeast and passed west of Vanuatu on 28th, changing direction to southeast on 29th towards New Caledonia. The average winds recorded at Ouanaham (New Caledonia) were 90 km/hr, with momentary gusts up to 136 km/hr. The system once again changed direction to move southwest affecting southern parts of New Caledonia from 30th till 31st.

‘Cilla’ formed on 27th January 2003 from a depression just southeast of Fiji’s Lau Group, which was affected by Ami earlier in the month. It tracked east to affect the central Tongan island group of Ha’apai on the same night. Cilla was a short-lived cyclone, which trailed past just south of Niue on the 28th and weakened to a tropical depression.

Acknowledgement to all National Meteorological Centres in Pacific for provision of information on Tropical Cyclones for current season.

Tropical Cyclones from November 2002 through January 2003.