Update, 7.30pm: Two homes have been lost and residents are being urged to leave immediately as a "deadly" fire burns near Bridgetown this evening.
An emergency warning has been issued for residents south of Hay Road, west of South Western Highway, north of Brockman Highway and east of Wetherley Road.
The warning area spans the shires of Donnybrook-Balingup, Bridgetown-Greenbushes and Nannup and includes the townsites of Greenbushes, Hester Brook, Wandillup, Maranup, Southampton and the western part of Bridgetown.
The Department of Fire and Emergency Services says homes in the area are under an immediate and direct threat by fire.
DFES has confirmed two homes have been destroyed in the blaze, including the Southampton Homestead - a bed and breakfast and farm north west of Bridgetown - and a home 900m away.
The fire started at the Blackwood River in Southampton and has crossed the river, moving east. The blaze is burning in bushland, plantations and farmland and has destroyed about 1700 hectares.
Fire crews are expecting a wind change from north westerly to south westerly, moving the fire towards homes in Greenbushes.
The fire is one of seven that started from a lightning storm in the area yesterday.
The Department of Fire and Emergency Services warns that residents’ lives are in danger and they needed to act immediately to survive.
"If the way is clear, leave now for a safer place. Do not wait and see, leaving at the last minute is deadly," the DFES warning says.
People in the Shire of Bridgetown-Greenbushes that decide to leave are to place a green bag on their mail box or gate so fire fighters know they have left.
DFES Deputy Incident Controller Danny Mosconi said the terrain and wind made it difficult for 150 firefighters to contain the blaze. Fire crews are constructing containment lines on the north eastern flank of the fire.
“At the peak of today there were nine separate fires and crews have been working all day to get it under control.”
“The terrain makes it very difficult to gain any accessibility and some of the fuel loads in the area we are talking about are very high.”
Six water bombers and two helicopter are also at the scene battling the blaze.
Residents have been advised to leave via Southampton Road and take Brockman Highway or Maranup Ford Road to Bridgetown.
If people are unable to take shelter in their homes, they should head towards the nearest open space, swimming pool or dam.
A relocation point has been set up at Bridgetown Recreation Centre and a community meeting will be held for residents at the centre at 5pm. Western Power says some homes have been left without electricity during the fire.
Greenbushes Primary School will be closed tomorrow.
Road closures are in place on Southampton Road between Hay Road and Maranup Ford Road, Maranup Ford Road between the mine site access road and Brockman Highway and Spring Gully Road between Greenbushes and Southampton Road.
Motorists are being asked to avoid the area.
The Bibbulmun Track is closed between Balingup and Donnelly River Village.
A 'watch and act' warning has also been issued for people west of Greenbushes-Boyup Brook Road, Kendall Road, Winnejup Road, Wheatley Giblett Road, Carbanup Brook Road and north of Glentulloch Road/
DFES says there is a possible threat to lives and homes as a fire approaches the area and due to changing conditions. People are being encouraged to leave the area or prepare to defend their homes.
Homes are also threatened by an out of control fire near Kin Kin which started during last night's storms.
An 'advice' warning for the area has been upgraded to a 'watch and act' for people east of Wheatley Coast Road, north of South Western Highway, south of Muirs Highway and west of Strachan and Curtin Roads. Homes in Quinninup are not under threat.
The fire is burning quickly towards Muir Highway and DFES said it was "out of control and unpredictable".
DFES says homes to the north-east could be threatened by fire due to a wind change.
The blaze is being fought by 80 fire fighters, three bulldozers and two fixed-wing water bombers.