OSCAR

History

Tropical Cyclone Oscar began as an early-season tropical low that formed within an active monsoon trough in the eastern Indian Ocean, south of Java and in the vicinity of Christmas Island, on 28 December 1993. Steering currents were weak, and the disturbance drifted slowly south-eastward across warm water for several days, organising only gradually through the end of December and into the new year.

The system consolidated sufficiently to be named Oscar by the Bureau of Meteorology's Tropical Cyclone Warning Centre in Perth on 3 January 1994, at which point it lay roughly 600 km north of Broome. Oscar then adopted a west-south-westward course that took it parallel to the Kimberley and Pilbara coastlines, remaining well out to sea. It reached Category 2 intensity on 4 January, with a minimum central pressure of about 980 hPa, maximum 10-minute sustained winds near 100 km/h and gusts to around 140 km/h. This peak strength was maintained over the North West Shelf until 6 January. Some assessments regard Oscar as a marginal system that held cyclone intensity only briefly.

Late on 6 January increasing upper-level westerly shear and the intrusion of dry mid-level air stripped the deep convection away from the low-level centre, and Oscar fell below tropical cyclone strength on 7 January. The remnant low drifted southward over open water to the west of Shark Bay before dissipating on 9 January, ending a life cycle of close to two weeks from initial genesis.

Oscar never made landfall and stayed between roughly 300 and 500 km offshore throughout its active phase, so mainland impacts were minimal. Outer rainbands brought localised squally weather and rough seas to exposed beaches between Broome and Port Hedland. Offshore oil and gas operators on the North West Shelf took precautionary measures as the Category 2 system passed, including temporary production shutdowns and the evacuation of non-essential personnel from rigs and platforms. No deaths, injuries or structural damage were reported on land.

Sources: Bureau of Meteorology report Wikipedia