Lives and homes are in danger as blazes rage north-east of Perth in Julimar and in Gwindinup - in WA's South West - on Australia Day.
The Department of Fire and Emergency Services issued an emergency warning for people living in Gwindinup in an area east of South West Highway north of Argyle Road, and near Myrtle Ridge, Hetherington Road, Hooker Street , Hurst Road and the surrounding areas.
The bushfire, which started near the intersection of Hurst Road and Hooker Street, is unpredictable and out-of-control and is moving fast in a south-easterly direction. Burning embers are likely to be blown around properties.
DFES urges people to act immediately to survive and to leave their homes if the way is clear and not to wait until the last minute, which could prove deadly.
People who plan to actively defend their properties are warned not to rely on mains water pressure.
Those who are unable to leave should get ready to shelter in their homes.
DFES also warns not to return to the area. If you cannot shelter in your home, a safer place you can go to is a local open space, beach, shed, swimming pool, dam or building. The safest option may be to visit family or friends who live away from the area.
The Department for Child Protection and Family Support has set up a temporary evacuation centre at Donnybrook Recreation Centre on Steer Street in Donnybrook.
A number of roads in the Gwindinup area had been closed and aerial support was called in to assist firefighters.
Hurst Road is closed in both directions between Gwindinup Road to Argyle Road.
Around 30 fire-fighters are battling the blaze.
A fast-moving and unpredictable bushfire is also threatening lives and homes in the Shire of Toodyay on Thursday.
The Department of Fire and Emergency Services has issued a watch and act alert for people in Julimar between Bindoon-Dewars Road and Julimar Road, and in the vicinity of the western boundary of Julimar state forest.
People need to leave or get ready to actively defend their property, DFES said.
The fire, which started near the intersection of Cooks Road and Northern Boundary road is fast moving towards the Julimar state forest. Conditions are changing and aerial support has been called in to support firefighters.
Roads in the area have been closed.
The cause of the fire is yet unknown.
For more information visit emergency.wa.gov.au, call 13 DFES (13 3337), follow DFES on Twitter @dfes_wa, or listen to news bulletins.
Meanwhile a man has been arrested as part of Toodyay detectives' investigations into a bushfire which broke out early on Thursday morning.
Police spokeswoman Susan Usher said DFES were called to as blaze at the north end of Dewars Pool Road in Perth's north east.
Toodyay Police and Wheatbelt detectives are investigating the circumstances of the blaze.
A 41-year old man is in custody, assisting with their inquiries.