NATHAN

History

Tropical Cyclone Nathan was a short-lived late-season system that spent its entire life over the open waters of the Coral Sea, well clear of the Queensland coast.

Nathan developed from a persistent tropical low that had become embedded within an active monsoon trough over the northern Coral Sea on 20 March 1998. Conditions were favourable enough for gradual consolidation, and the Brisbane Tropical Cyclone Warning Centre named the system Nathan on 21 March, when it reached Category 1 intensity roughly 400 km to the northeast of Cairns while drifting east-southeastward.

With only light vertical wind shear over the region, the cyclone continued to organise while executing a slow, meandering loop over open water to the east of Cape York Peninsula. Nathan reached Category 2 strength on the Australian scale on 23 March and held that intensity through 24 March. At its peak it had an estimated minimum central pressure near 980 hPa, with maximum 10-minute mean winds of about 100 km/h (55 knots) and gusts to approximately 140 km/h.

The favourable environment did not last. An approaching upper-level trough drove strong westerly shear and dry air into the system on 25 March, and the deep convection quickly separated from the low-level circulation. Nathan was downgraded to a tropical low late that day. The exposed remnant circulation drifted eastward into the central Coral Sea and had dissipated entirely by 26 March.

Because Nathan stayed several hundred kilometres offshore for its whole active life, mainland impacts were negligible. Outer cloud bands and squally winds brushed sections of the Cape York coast, but there were no damaging coastal winds and no structural damage. Willis Island, in the central Coral Sea, experienced strong gale-force winds and heavy seas as the cyclone passed through the region, and marine warnings were issued for high-seas shipping routes. No deaths or injuries were attributed to the system.

Nathan was one of the final cyclones of a 1997–98 Australian region season that produced slightly fewer systems than average.

Sources: Bureau of Meteorology report Wikipedia