ex-tropical cyclone narelle

Ex-Tropical Cyclone Narelle: What to Expect as Storm Eyes Perth

Western Australia is bracing for another major weather event this week. After making a rare crossing of the Australian continent—a feat not seen in decades—Ex-Tropical Cyclone Narelle has weakened below tropical cyclone strength but is now forecast to reform over the west Kimberley coast and potentially curve back toward the southern WA mainland, with Perth emerging as a possible target.

The storm’s unusual trajectory has captured national attention, not just because of its intensity and rainfall totals, but also due to how rarely cyclones cross from east to west across the continent. While the system has already caused significant flooding and disruption in the Northern Territory, authorities are warning that the emergency isn’t over—especially for communities along the WA coastline.

Main Narrative: A Once-in-a-Generation Cross-Continent Journey

Cyclones typically form off northern Australia’s warm waters and move southwest or west-southwest, often dissipating before reaching inland regions like Western Australia. However, Ex-Tropical Cyclone Narelle broke this pattern by intensifying over the Gulf of Carpentaria, crossing Queensland, weakening into a tropical low, then re-intensifying after entering the Indian Ocean near Darwin.

This rare “cross-continent” journey means Narelle will be delivering two separate rounds of severe weather—first across the Top End and now potentially again along the Pilbara and Gascoyne coasts before possibly veering south toward Perth.

As it moved inland over the Northern Territory over the weekend, Narelle dumped more than 200 millimetres of rain on already saturated areas, triggering flash floods and prompting evacuation alerts in Katherine and surrounding communities. The NT Emergency Services Agency reported widespread road closures and power outages, with residents describing scenes of submerged homes and washed-out infrastructure.

Now, as the system transitions into Western Australia, forecasters warn it could rapidly redevelop into a new tropical cyclone—potentially reaching Category 1 strength—before turning south. If it maintains that track, Perth and surrounding suburbs may face damaging winds and heavy rainfall later this week.

“We’re seeing conditions that haven’t occurred in modern meteorological records,” said Dr. Sarah Jenkins, senior meteorologist at the Bureau of Meteorology (BOM). “When a cyclone crosses the continent like this, it loses its original energy source but can sometimes tap into new oceanic heat—especially in the Timor Sea—and rebuild quickly. That makes forecasting tricky.”

Recent Updates: Timeline of Key Developments

March 20–21: Tropical Cyclone Narelle forms over the Coral Sea and strengthens to Category 3, impacting coastal communities in far north Queensland.

March 22: Narelle weakens to a tropical low after crossing into the Gulf of Carpentaria and making landfall near Borroloola in the Northern Territory.

March 23: Heavy rainfall triggers severe flooding across Katherine and surrounding regions. The BOM issues a Severe Weather Warning for the Top End, while ABC News reports that over 200mm of rain fell within 24 hours.

March 24: Ex-Cyclone Narelle continues westward across the NT, now classified as a tropical low. Authorities warn the emergency is "not over," with further flooding expected in low-lying areas.

March 25: The system enters Western Australia’s North West Shelf region. Forecasts suggest redevelopment is likely off the west Kimberley coast within 48 hours.

March 26–27: If conditions remain favorable, the reformed system may begin moving south along the WA coast. Perth is flagged as a potential impact zone, though models show some uncertainty in exact timing and intensity.

According to verified news reports from ABC News, The Guardian, and SMH.com.au, the storm remains under active monitoring. The BOM has advised all coastal communities from Broome to Geraldton to stay alert and review emergency plans.

Contextual Background: Why This Matters

While tropical cyclones are common in northern Australia during the wet season, a system crossing entirely from the Pacific to the Indian Ocean is exceptionally rare. Historical records show only a handful of such events since 1900, with none occurring as recently as the past 50 years.

One notable example was Cyclone Tracy in 1974, which devastated Darwin but did not continue across the continent. More recently, Cyclone Jasper in December 2023 brought record-breaking rainfall to Far North Queensland but dissipated before reaching Western Australia.

What sets Narelle apart is not just its path, but its ability to persist through multiple stages—tropical cyclone, tropical low, then redevelopment—thanks to favourable atmospheric conditions and ocean temperatures exceeding 29°C in parts of the Timor Sea.

“Most cyclones lose their identity once they hit land,” explained Professor Michael Reeder from the University of NSW’s Climate Change Research Centre. “But Narelle’s journey shows how climate variability can create novel weather scenarios. It underscores why preparedness matters more than ever.”

The broader implication? As global sea surface temperatures rise due to climate change, meteorologists warn that extreme weather systems may become more unpredictable. Systems could strengthen faster, shift tracks unexpectedly, or exhibit behaviors not previously observed.

For WA, this means updating risk assessments and ensuring local councils have robust contingency plans—particularly for remote Indigenous communities in the Pilbara and Gascoyne who may lack immediate access to emergency services.

Immediate Effects: Flooding, Disruption, and Community Response

So far, the most severe impacts have been felt in the Northern Territory. Katherine, a town of about 6,000 people located on the Stuart Highway, became one of the hardest-hit locations. Residents reported waist-high floodwaters in residential streets, with several houses requiring evacuation.

“I’ve lived here my whole life and I’ve never seen anything like this,” said local shop owner Maria Lopez, whose business sustained water damage. “The river swelled so fast—within hours it went from manageable to catastrophic.”

NT Police confirmed that over 300 people had sought refuge in temporary shelters by Monday afternoon. Power outages affected nearly half of Katherine’s population, and essential supplies—including fuel and groceries—were running low in isolated pockets.

Meanwhile, in Western Australia, precautionary measures are underway. The Department of Fire and Emergency Services (DFES) has pre-positioned crews and equipment along the northwest coast. Local governments in Broome, Port Hedland, and Exmouth have issued public advisories urging residents to secure loose items, avoid flooded roads, and monitor official updates.

Schools in selected areas—including Karratha and Carnarvon—will remain closed until further notice, and ferry services between Perth and Rottnest Island were suspended on Tuesday morning due to deteriorating conditions.

Economically, the storm poses risks to agriculture, mining, and tourism sectors. The Pilbara region accounts for nearly a third of Australia’s iron ore exports; any prolonged shutdowns at port facilities could affect global supply chains. Similarly, tourism operators fear cancellations ahead of the Easter holiday period.

Future Outlook: What Could Happen Next?

Forecast models from the BOM and international agencies such as the US National Hurricane Center show divergence beyond 72 hours, reflecting the inherent complexity of cross-continental cyclogenesis. However, consensus points to three main scenarios:

Scenario 1: Reform and Head South Toward Perth

If ocean temperatures remain high and vertical wind shear stays low, Narelle could intensify to a Category 1 cyclone by Thursday night. In this case, Perth metropolitan areas—particularly those near the Swan River estuary—would receive heavy rain and gale-force winds between Friday and Saturday.

Scenario 2: Dissipate Over the Interior

Warmer-than-average land temperatures and dry air intrusion might prevent full redevelopment. The system would weaken into a broad area of showers and thunderstorms, delivering localized downpours without sustained cyclone-force winds.

Scenario 3: Curve Eastward Into the Southern Ocean

A high-pressure system strengthening over the Great Australian Bight could nudge the storm east, sparing WA but bringing unsettled weather to South Australia and Victoria.

Regardless of the outcome, authorities stress that even if Narelle doesn’t directly strike Perth, residual effects—such as large waves, rough surf, and hazardous driving conditions—will linger through the week.

Emergency Management Australia has activated its National Coordination Centre to support state responses. The Red Cross and Salvation Army are mobilizing volunteers to assist with welfare checks and distribution of relief supplies.

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