Firefighters contain multiple blazes as bushfires destory homes in WA

Two homes have been destroyed by a blaze south of Perth as firefighters warn residents to remain vigilant for bushfire threats.

Multiple blazes across Western Australia are testing firefighters, with authorities warning there are more "difficult" days ahead. Credit: Supplied

A blaze that destroyed two homes south of Perth has been brought under control but firefighters urge people to remain vigilant for bushfire threats.

Seven emergency-level bushfires have engulfed homes and torn through bushland, rural properties and suburbs on Perth's fringes in the past three days.

Authorities confirmed two more homes had been lost while crews battled a fire at Keysbrook, south of Perth. Both were believed to be empty.

Crews in WA have faced "intense fire behaviour" driven by strong and gusty winds and low humidity. Source: AAP / Aaron Bunch

The fire was burning at watch-and-act level before being downgraded on Saturday evening, though an advice warning remains for parts of Keysbrook, Nambeelup and North Dandalup.

Residents were told to remain vigilant and stay up to date with the latest warnings.

"Weather conditions over the next few days will put pressure on containment lines, potentially increasing fire activity in the area," the alert reads.

Department of Fire and Emergency Services incident controller Russell Wells said crews were rotated on Saturday to allow firefighters time to rest.

Resources were bolstered for the evening, he said.

Residents in WA have been told to remain vigilant and stay up to date with the latest fire warnings. Credit: Supplied

Difficult terrain and homes spread out across a wide area were proving challenging for ground crews, with aerial assets used to spot fires and determine the best place to deploy resources.

In the state's southwest, parts of Callcup, Crowea and Meerup also remained on high alert amid a watch and act notice as crews worked to contain the fireground.

Heatwave conditions in some parts of the state are waning, with the worst of the extreme heat now pushing into the Northern Territory.

But the weather bureau said there will still be severe heatwave warnings in place for WA for a while to come.

"Severe heatwave conditions over much of northern and central WA continuing into next week," the bureau warned.

"Locations likely to be impacted include Kununurra, Marble Bar, Newman and Wyndham."

High fire danger ratings have been forecast on Sunday for 38 districts across the state, the third highest classification.

The fire danger level is expected to rise to extreme in Brockman and Swan Inland North on Christmas Day.