Australia Weather News

Perth and large parts of Western Australia's south are preparing to batten down the hatches ahead of a severe storm set to pummel the region this weekend.

With a strength only seen every three to five years, the intense weather system could bring destructive wind gusts of more than 125 kilometres per hour and heavy rainfall to a large swathe of WA's coast.

The wild weather will first hit the Central West near Kalbarri on Saturday evening, before barrelling over the southern part of the state, including Perth, on Sunday morning. 

Bureau of Meteorology (BOM) duty forecaster, Joey Rawson, said residents in the state's south-west should take the time to prepare their properties before the severe weather arrives.

"[Sunday] afternoon is when those winds are really going to strengthen and if there's any loose objects around the place today, before the weather starts really closing in. It's a good time to get that all sorted," he told 102.5 ABC Radio Perth.

"It's been a while since such a significant system has impacted the south-west of the state.

"[When you see] systems that you've not seen for a long time you know it does rattle you a little bit because you know that there's a potential that if things aren't prepared for, then there could be some serious consequences.

"So there's potential for trees coming down there's the potential for people to lose [their lives] if they're not prepared.

"We're looking at waves potentially getting to 8 to 9 metres along the west coast and tomorrow morning we've also got a really high tide that's pushing up against the west coast.

"So places like Riverside Drive in the city will have water inundation across the road and also places along the west coast that are lower lying potentially may have water approaching as sea levels rise."

Ferries cancelled

All Rottnest ferries have been cancelled on Sunday when waves of up to 9m are expected to cause beach erosion and flooding along the west coast.

Rainfall of up to 50 millimetres is expected in coastal areas, which will ease as the system moves east, he said. 

The wet weather comes as much of the southern half has experienced below-average rainfall across the month. 

BOM senior meteorologist Jessica Lingard said it was the first significant weather system for this time of year and could be destructive.

“We’ve had a very dry autumn, and then you get a system like this that will bring a lot of damage with it, a lot of tree branches will come down, some of those more brittle trees will potentially be knocked over," she said.

“The last time we had a weather system this strong come through, there were about 600-odd calls for help for the SES, so we’re expecting similar levels for requests for help."

She said conditions could be quite dusty in parts of the Great Southern and Central Wheatbelt on Saturday, ahead of the cold front arriving.

Flash flooding possible

A number of severe weather warnings have already been issued for residents along WA's south coast.

Heavy rainfall could lead to flash flooding in the central west district area, with six-hourly rainfall totals expected to reach 60mm.

Damaging surf conditions expected over the weekend could lead to coastal erosion between Gregory, south of Kalbarri through to Cape Leeuwin.

Travellers warned 

Department of Fire and Emergency Services assistant commissioner Paul Carr said those travelling in the region over the long weekend should take precautions.

"We also urge long weekend travellers who may be travelling in areas where there is heavy tree foliage along road verges or camping in areas underneath trees to be wary of the weather coming and take action where needed," he said.

He said residents in the South-West and Great Southern should lock down loose objects around their homes and trim overhead branches as early as possible.

"Make sure that you have your emergency kits ready," he said.

"Charge up all your devices before the weather comes in. Get a battery-operated radio, because if the power does go out, you will actually need that to listen to the alerts and warnings."

Perth's forecast: