Tropical Cyclone Narelle has moved into the Indian Ocean off Western Australia and is forecast to rapidly intensify back into a tropical cyclone, approaching the west coast of WA later this week. The system represents a rare threat to Australia's populous south-west after an extraordinary journey across the continent's north.
As it approached Queensland, the storm intensified to a category 5 on Australia's tropical cyclone scale with maximum sustained winds up to 225 kilometres per hour. It crossed into Western Australia's Kimberley region on Monday, sweeping past the remote town of Wyndham and the Indigenous community of Kalumburu as it tracked south-west. The weather system, which weakened to below cyclone strength after making landfall in the Northern Territory on Sunday, has dumped heavy rain across the Top End, but caused much less damage than expected.
The Bureau of Meteorology predicts Narelle to become a tropical cyclone once again by Wednesday morning and reach category 3 strength by Wednesday night, then become a category 4 tropical cyclone as it tracks to the north of the Pilbara on Thursday, with even a chance it will get stronger and become a category 5 tropical cyclone later this week. This WA landfall will most likely occur on Sunday somewhere near or to the north of Perth.
A tropical cyclone this far south in Western Australia is a rare occurrence; the last time this happened was in 2021 when Tropical Cyclone Seroja crossed the coast near Kalbarri as a severe category 3 system causing widespread damage. According to the Bureau, 14 systems that had been classified as tropical cyclones brought gale force winds, or caused property damage, in Perth between 1910 and 2024.
The forecast rainfall could be significant for Perth's water security but also poses flooding risks. Perth residents should prepare for widespread falls of 20 to 50 millimetres on Saturday, with an additional 20 to 30 millimetres possible on Sunday, though totals could climb higher depending on the system's exact track. Up to 100 millimetres of rain is possible between Geraldton and Perth.
There is still a range of possible scenarios of where Narelle could track, including a rare coastal crossing close to Perth. One scenario includes the cyclone hugging the northwest coast or remaining farther offshore before crossing closer to the southwest. The models will continue to update in the coming days, and so will BOM's forecasts; regardless of which path Narelle takes, the western and south-western parts of WA will likely be affected this week.
The Bureau of Meteorology said it is the first time since 2005 that a single cyclone has affected all three of Australia's tropical regions in one event. This triple-strike pattern remains exceptionally unusual in Australian weather history, emphasising the complexity of the atmospheric conditions driving Narelle's extended track.