A tropical low formed in the Kimberley region near the Western Australia (WA) – Northern Territory border, about 190 kilometres (km) south-east of Kununurra on Monday 3 February 2020. The low tracked west and moved offshore near the Dampier Peninsula north of Broome during 5 February. Once over water it gradually intensified till it reached cyclone category 1 strength at 2.00pm on 6 February and was named Tropical Cyclone Damien. As Damien moved west-southwest during the morning of 7 February it intensified rapidly, developing from a category 1 to a category 3 system in just nine hours.
In preparation for Damien’s impact, WA’s Department of Fire and Emergency Services deployed additional resources to the region. Public information and emergency warnings were issued regularly, evacuation centres were set up in Karratha and South Hedland, and residents urged to activate their cyclone plans.
Damien moved south towards the Pilbara coast on 7 February and made landfall as a category 3 severe tropical cyclone around 3:30pm on 8 February over the Karratha-Dampier region; the strongest cyclone to make landfall in the area since 2013.
Damien’s eye moved directly over Karratha, population approx. 16,000, on the Saturday afternoon. Destructive winds gusting close to 200 kilometres per hour (km/h) blew for two hours either side of the cyclone’s eye as it passed over the city. Accompanied by torrential rain, trees were uprooted, windows smashed and roofs lost, and the cyclone left about 9500 customers temporarily without power across the Pilbara.
Wide-spread damage prompted many calls to the State Emergency Service requesting assistance. There were 180 reports of damage from wind, 68 from fallen trees and 116 reports of damage from water ingress. The Bureau of Meteorology's Dampier radar sustained significant damage during the passage of Damien.
Barrow Island, Mardie, Varanus Island, Karratha Airport, Roebourne Airport and Legendre Island all reported sustained gales that day, with Karratha Airport recording the highest wind gust of 194 km/h at 2:31pm, the strongest gust for that site in 17 years of records.
The system continued to move inland, weakening on 9 February, and the remnant tropical low then tracked south-east over WA’s inland Pilbara, eastern Gascoyne and northern Goldfields regions.
Heavy rainfall caused flooding initially through the Kimberley when the system was a tropical low, then through the Pilbara and eastern Gascoyne regions. Widespread totals of 100 to 200mm and isolated falls up to 235mm were recorded near the Pilbara coast. Notable rainfall totals in the 48 hours to 9.00 am on 9 February included Karratha Airport 235.2mm and Roebourne Airport 234.8mm. Ginginjibby recorded 153.2mm in the 72 hours to 9.00am on 11 February.
Rivers and catchments that experienced increased flows included the West, North and Eastern Kimberley, Ashburton, Pilbara coastal streams, Fortescue, Gascoyne, Murchison, De Grey and the Salt Lake Rivers District.
Damien delivered rainfall and river flows to pastoral areas that had been drier than average for at least two years, and filled many dams and water resources including the Harding Dam, the main water supply for the Karratha and Dampier areas.
Severe tropical cyclone Damien was the third tropical cyclone and the second severe tropical cyclone in the Australian region for the 2019-20 season.
The Australian Government made disaster recovery funding available for individuals, primary producers and small businesses in seven local government areas in WA impacted by Damien, as well as for counter disaster operations and the reconstruction of essential public assets.