A tropical low in the Timor Sea could strengthen into a tropical cyclone before landfall early on Saturday.
A low that developed in the western part of the Timor Sea on Tuesday evening has set its sights on the northern coast of Western Australia.
As it slowly moves southward, the low will be moving over warm waters into an area of lower wind shear.
"These conditions are favorable for development into a tropical cyclone," AccuWeather Senior Meteorologist Jason Nicholls said. "This should allow the low to become more organized into early Friday."
If the low moves slowly enough towards the land, the extended time over the water could allow a weak tropical cyclone to develop before making landfall.
Sustained winds in such a tropical cyclone would be 63 to 88 km/h (41 to 55 mph) with gusts as high as 125 km/h (78 mph).
If the low does not have enough time to strengthen, winds will likely be below 60 km/h (40 mph).
"The strongest winds should be closer to the storm track," Nicholls added.
This means the greatest risk for impact winds will be near where the storm makes landfall and especially along the coasts.
Whether the storm can organize into a tropical cyclone or not, heavy rainfall is also expected.
Especially from Karratha to Port Headland, rainfall amounts from 75-150 mm (3-6 inches) are likely. Higher amounts could be possible in the heaviest bands if the storm reaches cyclone strength.
Some outer bands of the storm could reach as far as the city of Telfer. However, the strongest winds and heaviest rain will remain farther north and west.
By early on Sunday, the system will track even farther south, losing strength the longer it is over land.
The moisture will be picked up by a front moving through Perth earlier in the weekend, dragging rain into southeastern parts of Western Australia into Monday.