Cyclone Perth threat as ex-Tropical Narelle could reform and curve back to coast — rare inland crossing raises alarms
Ex-Tropical Cyclone Narelle has weakened across the Northern Territory but forecasts now raise the prospect of cyclone perth impacting regions much farther south after a rare transcontinental crossing. The system dropped more than 100mm across wide areas of the Territory, closed the Stuart Highway near Adelaide River and is expected to move offshore before potentially regaining strength and tracking toward the Western Australia coastline this week.
Background and context: a rare westward trek across the continent
Narelle fell back to a tropical low after bringing heavy rain to already-saturated parts of the Northern Territory. That rainfall prompted flood alerts and warnings for several communities, with Daly River, Adelaide River and Katherine placed at risk of minor to major flooding following the heavy falls. More than 100mm fell across a wide area, and rising river systems closed several roads, including the main Stuart Highway near Adelaide River.
Bureau of Meteorology forecasts show the system tracking into the Indian Ocean on Tuesday evening and then travelling south parallel to the Western Australia coastline. The bureau indicates the low could spend significant time over water and move into a favourable environment to re-intensify into a tropical cyclone and then a severe tropical cyclone by Wednesday evening.
Cyclone Perth: trajectory, intensity forecasts and local risks
Forecast guidance cited by the bureau gives reasonable confidence that Narelle will move offshore around the Pilbara coast and, while over water, could regain strength rapidly. Models suggest the system could become a major category four offshore by Thursday, bringing coastal impacts from strong and damaging winds. Ilana Cherny, meteorologist at the Bureau of Meteorology, warned of damaging gale-force winds and gusts up to 100km/h as the system moves into the northern Kimberley region, with heavy rain and risks of both riverine and flash flooding.
By Friday the forecast track shifts the risk zone further south into central and southern parts of Western Australia, with reduced confidence beyond that point. Cherny noted that once the system moves closer to the coast near the weekend, there is potential for a crossing again — a scenario that could put cyclone perth into reach of agricultural districts north of Perth and, potentially, coastal communities farther south. The bureau emphasised a range of scenarios remains possible as the system approaches the WA coastline.
Expert perspectives, implications and what to watch
Concern among regional leaders and forecasters has focused on the system’s speed across the continent and the scope for re-intensification offshore. Lia Finocchiaro, Northern Territory chief minister, said: “As we are all very relieved to learn, ex-Tropical Cyclone Narelle is now very close to the West Australian border and we bid her farewell, and hope that everyone in WA will be OK. ” That statement underlines both the relief in the Territory and the growing attention in WA as the system continues west.
Ilana Cherny, meteorologist at the Bureau of Meteorology, stressed the meteorological drivers behind the projected re-strengthening: “It’s going to spend significant time over water and will move into a favourable environment to re-intensify into a tropical cyclone and then a severe tropical cyclone. ” She added caution about late-week uncertainty: “Once we get into Friday and the weekend, the system starts to track closer to the coast with a potential crossing again. But at this stage it is too early to know if it will cross or if it will still be a tropical cyclone. ”
Practical implications are already visible: communities in the far north faced flood alerts and road closures after heavy rainfall, and the forecast intensification offshore could bring strong winds and coastal impacts. Forecasters also noted the potential for welcome rainfall in agricultural districts north of Perth, even as the possibility of stronger coastal impacts remains a source of concern. It is unusual to see a system that may impact so far south, but meteorologists note there are examples of such tracks.
As emergency services and communities monitor model guidance and bureau updates, the chief uncertainties are the exact coastal track and timing should the system reform. With forecast windows narrowing through midweek, officials have highlighted both the flood legacy in the Territory and the need for WA preparedness if cyclone perth moves closer to shore this weekend. What will determine final impacts is whether the system maintains tropical cyclone intensity as it approaches the coast, and how closely its track follows the western shoreline into the weekend?
