Bushfire emergency continues in Perth's north as firefighters seize ...

Fire crews have spent a second night battling a large bushfire in Perth's north-east, with better conditions offering some respite for residents and authorities.

Key points:An emergency warning remains in place and 10 homes are confirmed lostFavourable conditions overnight helped crews reduce some warning areasBut there are fears about a likely wind change on a day expected to hit 35C

The blaze began on Wednesday in the Gnangara Pine Plantation in the city's northern suburbs and quickly spread west, fanned by strong winds and extreme heat.

Despite the best efforts of firefighters, 10 homes and several other structures have been confirmed lost.

The majority of the destruction has been identified in the semi-rural suburb of Mariginiup, while residential areas in Tapping and Banksia Grove have also been hit.

An emergency warning remains in place for parts of Jandabup, Melaleuca, Wanneroo and Mariginiup.

The Department of Fire and Emergency Services (DFES) said on Friday morning that the fire was 95 per cent contained but remained uncontrolled.

"There's been favourable conditions overnight due to the lighter winds and high humidity, which means we've been able to reduce some of the warning areas," DFES incident controller Scott Hares said.

"But it's important that community members stay alert and go to Emergency WA to check where those boundaries are because conditions can change anytime."

Water bombers worked tirelessly to save homes from the fierce inferno.(ABC News)

After back-to-back days of temperatures touching 40 degrees Celsius, Perth experienced a cool change overnight as it fell to 19C just before 4am on Friday.

The city is expected to reach a maximum of 35C, but of greater concern to authorities is an expected change of wind direction from north-east to south-west.

The fire swept through large swathes of land in Mariginiup.(ABC News: Andrew O'Connor)

"[This morning] is critical to our effort," Mr Hares said.

"We're going to really work hard to consolidate containment lines in advance of that wind change."

With the evacuation centre at Quinns Rocks at capacity, authorities late yesterday opted to open the Bullsbrook COVID quarantine centre.

More than a dozen bushfire evacuees spent the night at the Bullsbrook COVID quarantine centre.( ABC News: Briana Shepherd )

Mr Hares said 19 people spent the night at the facility, while more were likely to be sent there as the fire remained a threat.

Fears of more property losses

In addition to the emergency warning, a watch and act alert stands for Sinagra, Ashby, Tapping and Banksia Grove.

Mr Hares said it was likely other properties had been lost, but the extent of the damage was yet to be fully identified.

"We've completed about 80 per cent of our rapid damage assessments and we're going to recommence them at first light," he said.

"To those that have lost their homes, your loss is felt very firmly by us. We stand with you in these difficult and stressful times."

More than 100 firefighters continue to battle the blaze across a front that now stretches for more than 50 kilometres.

With approximately 1,850 hectares of land lost, aerial bombers will resume their efforts to stop the spread of the blaze at first light.

The roof of this house crumpled like tin foil as the fierce blaze swept across suburbs. (ABC News)

Hundreds of other staff and volunteers are assisting the community and residents at the two evacuation centres in Bullsbrook and Quinns Rock.

Power has been disrupted across a wide area, with poles and wires brought down throughout the fire zone.

Western Power said more than 100 poles had been damaged, with the number set to rise once a full assessment can be completed.

Blaze leaves ground 'moonscaped'

DFES district officer Ryan Bulluss said the fire had left patches of ground very burnt with "absolutely nothing left behind".

"An adhoc term we use is 'moonscaped', because it's burnt with such an intensity and such a heat that it's left nothing behind," he said.

"What we're seeing out here is a complete bare moonscaping of the landscape, where all the fuel is removed and the ground is just left white with ash."

He said the last time he had seen a fire of such intensity was the Wooroloo blaze in Perth's east in February 2021.

"When we had the fire run from through Wooroloo and the hills there, [it was] the same sort of speed and ferocity and temperature running on the same sort of winds in the same sort of conditions," he said.

"Normally we wouldn't expect to see something of this intensity this early in the season."

Perth forecast:

Friday: 35C

Saturday: 22C-39C

Sunday: 22C-39C

Monday: 23C-34C

Tuesday: 20C-29C

Wednesday: 18C-29C

Thursday: 19C-33C

Visit Emergency WA, call DFES on 133 337, follow DFES on Twitter or listen to ABC Local Radio to stay up to date.