Late into the weekend, a low pressure system is expected to move across the Western Australian coastline with cyclonic conditions.
This afternoon, a tropical low is situated northwest of Western Australia, near the Cocos Islands, and will steadily move in a southeasterly direction while intensifying over the next 48 hours.
Whilst this system has a low chance of developing into a tropical cyclone, the low is expected to undergo a transformation into a extratropical cyclone (otherwise known as a mid-latitude cyclone).
At this stage, the low is likely to merge with an approaching cold front, dragging tropical moisture down from the Indian Ocean. This will lead to widespread rainfall across the western half of the state, with locally heavy falls of up to 100mm, along with potential for damaging winds gusts up to and exceeding 100km/h.
Some uncertainty still exists with the timing and intensity of this system, but widespread falls of 10-20mm are expected from Sunday into Monday.
In the wake of this system, cold and blustery southwesterly winds are expected, with further shower activity continuing into middle of the week.
Image 1: Projected tack, via Joint Typhoon Warning Center