On 15 March 2018, a tropical low formed in the western Arafura Sea. Drifting east-southeastwards north of the Tiwi Islands, the tropical low strengthened into a Category 1 tropical cyclone on the Australian scale early on 16 March, and was accordingly given the nameMarcus. In a generally favourable environment for intensification, Cyclone Marcus reached Category 2 status in the hours before it crossed the Northern Territory coastline, on 17 March. On 16 March, Marcus moved down towards the Australian coast, and rapidly intensified before making landfall in Darwin as a weak Category 2 tropical cyclone. Marcus intensified markedly upon moving away from the coast. Soon, the storm started to rapidly intensify, and by 21 March, Marcus reached Category 5tropical cyclone intensity. However, after doing so, the storm began to rapidly weaken due to a combination of an eyewall replacement cycle, stronger wind shear, and cooler waters. Marcus continued to rapidly weaken as it moved southward. The system soon transitioned into an extratropical cyclone on March 25, though Marcus' remnant would continue moving southeastward for another couple of days. On March 27, the extratropical remnant of Marcus dissipated off the southwest coast of Australia.
Preparation and impact
Before the storm, on 15 March, the Australian Bureau of Meteorology issued cyclone warnings for Darwin, the Tiwi Islands, and parts of the northwest Top End. Major events and flights in and out of Darwin were cancelled. Approximately 26,000 homes were affected by electricity outages as a result of the destructive winds, even in areas as far south as Batchelor and Adelaide River. Thousands of trees were destroyed across the Greater Darwin region including many African mahoganies planted after Cyclone Tracy for their fast growing and expansive shade qualities. Public schools and non-essential public service agencies were closed while the clean-up efforts continued and tree trunks removed from roads. Cyclone Marcus was the most destructive storm to hit Darwin since Cyclone Tracy caused devastation on Christmas Eve of 1974. The insurance loss were over A$85 million. In all, Marcus caused an estimated total of A$97.46 million in damages. The cleanup response was coordinated by the Northern Territory Emergency Services and included soldiers from the 5th Battalion and the 1st Combat Engineer Regiment of the Australian Army. The USMarine Rotational Force – Darwin also contributed to the clean up effort.
Retirement
Due to the damage caused by the cyclone in Darwin and its subsequent intensification, the name Marcus was retired.
