The system is described as an unusually strong and intense deep low, likely the strongest WA winter storm this year and potentially on a five-year cycle.

Officials stress coordinated action among government agencies, local governments, service providers and utilities, while urging communities to support one another through the event.

Coastal conditions will be hazardous, with offshore waves reaching up to eight meters and beach erosion likely around high tides on Sunday and Monday mornings.

Coastal rainfall could reach as much as 50 mm in some areas, contributing to flooding and erosion.

High tides are expected to raise water levels, risking flooding of low-lying coastal and estuarine areas, including the Swan River.

Offshore swells up to eight metres are anticipated, with coastal tides potentially flooding footpaths along sections of the Swan River; rainfall of 30–50 mm is forecast along the west coast, diminishing inland as the system moves east.

The unusually strong winter system is set to arrive from Saturday evening, impacting the central coast on Sunday and Monday.

Emergency officials urge West Australians to prepare now for winter storms and to plan for possible delays in emergency responses during the long weekend.

The Bureau of Meteorology notes this is a rare, intensive storm for southwest WA, possibly the strongest winter system of the year and potentially occurring only once every four to five years.

Warnings emphasize the exceptional nature of this event for the region, indicating it may be the strongest winter system WA sees this year.

A severe coastal winter storm is forecast to sweep Western Australia over the long weekend, bringing damaging winds of 90–100 km/h inland with coastal gusts exceeding 120 km/h and possibly surpassing 125 km/h along exposed shores.

Authorities warn this could be one of the strongest storms in five years, with heavy rainfall and powerful winds affecting the entire southwest during the long weekend.