Severe Tropical Cyclone Riley

21 January - 2 February 2019


Severe Tropical Cyclone Riley moved over waters off north-west Australia and did not directly impact the Australian coastline.

A weak tropical low was identified on 21 January in the Timor Sea moving to the south-west. The low gradually strengthened off the Kimberley coast, reaching tropical cyclone intensity on 24 January when it was located about 180 kilometres north-west of Broome.

Riley then moved on a general west south-west track roughly parallel to the Pilbara coast. Riley battled against ongoing easterly vertical wind shear but benefited from increased monsoonal inflow. This allowed it to strengthen into a category 2 tropical cyclone on 25 January then briefly category 3 intensity on 26 January before weakening. Riley re-intensified to category 3 intensity on 27 January and peaked that day when it was north of Exmouth.

Riley weakened from 28 January as it became disconnected from the moist monsoon flow and also moved over cooler waters. It weakened into a category 1 tropical cyclone on 29 January well to the north-west of Exmouth and then below tropical cyclone intensity on 30 January.

Although Severe Tropical Cyclone Riley did not directly impact the Australian coast, operations of the oil and gas industry off the north-west Australian coast were affected as the cyclone passed by. Tropical Cyclone Advices were issued for the north-west Kimberley coast between Kuri Bay and Beagle Bay and then for the Pilbara coast between Whim Creek and Exmouth for potential gales should the cyclone have tracked closer to the coast than expected.

For more information see the TC Riley Report (pdf).

Track and Intensity

Best Track of Tropical Cyclone Riley