Severe weather warning: Once-in-a-decade storm expected to hit Mandurah on Sunday afternoon, evening

The Bureau of Meteorology advised a tropical system is combining with a cold front and trough to produce a vigorous weather system that will affect the length of the west coast on Sunday and Monday.

A deep low pressure system is expected to pass near the South West of the state Sunday night, with the possibility of other lows forming along the trough as it impacts western parts of WA during Sunday.

Widespread severe weather, including damaging winds with peak gusts around 100 kilometres per hour, is likely.

The winds, which will average 60-70 kilometres per hour, are expected to hit Mandurah on Sunday afternoon and evening.

Locally dangerous winds with peak gusts of around 130 kilometres per hour kilometres per hour are also possible overnight, which could cause significant damage to homes and property.

These winds are expected to ease on Monday.

Heavy rainfall is expected from Sunday afternoon, with isolated rainfall totals to around 70 millimetres.

A dangerous storm tide with damaging waves and dangerous flooding and surf conditions is also possible.

EARLIER: West Australians are being urged to prepare their homes and reconsider intrastate travel this weekend as the Bureau of Meteorology warns of a severe storm set to hit the coast tomorrow.

A severe weather warning has been issued as a tropical system combined with a cold front is expected to produce one or two deep low pressure systems.

Widespread severe weather is expected to hit western parts of WA, including Mandurah and the South West, on Sunday.

Damaging winds with peak gusts up to 100 kilometres per hour are likely and could cause damage to homes and property.

These are forecast to develop in coastal areas between Onslow and Kalbarri from early Sunday morning and extend southwest to Mandurah during Sunday afternoon and evening.

Locally dangerous winds with peak gusts of around 130 kilometres per hour are also possible near the low pressure systems during Sunday afternoon and overnight.

Heavy rainfall may occur southwest from Kalbarri to Albany from Sunday afternoon with isolated rainfall totals to around 70 millimetres.

Tides are likely to rise significantly above the normal high tide mark with damaging waves and dangerous flooding as well as damaging surf conditions.

If you live in parts of the Gascoyne, Central West, Lower West, South West, South Coastal, Great Southern, Central Wheat Belt and parts of Pilbara, Goldfields and South East Coastal districts, you need to get ready now for the severe weather coming tomorrow.

Locations along the coast which may be affected stretch down from Exmouth, Carnarvon and Geraldton, down to Mandurah, Margaret River and east to Esperance.

RAC claims manager Glen Walker said Sunday's weather was predicted to be similar to a storm in June 2012, which brought in almost 10,000 RAC insurance claims at a cost of $15.5 million.

"Our advice is to take a look around your front and back yard for any potential risks and try to minimise them as much as possible," he said.

"The most common items damaged in a storm include fences and gates, ceilings, rooves and patios, which is why it's important to prepare your home in advance, including securing any loose items around your property such as trampolines.

"It's also a good idea to clean your gutters, down pipes and drains, and pump out some water from your pool to reduce the risk of overflow."

DFES is monitoring the situation.

DFES has these tips to help you and your family get ready now:

After a storm SES volunteers make temporary repairs to homes that have been badly damaged, such as roofs that have been ripped off or large fallen trees on homes or cars. Please contact your insurance company to organise permanent repairs.

KEEP UP TO DATE:

Visit www.emergency.wa.gov.au, call 13 3337, follow DFES on Twitter or Facebook or listen to news updates.

Updates will be provided when the situation changes.