The community's 100 or so residents were warned it was too late to flee homes and they were urged to take shelter inside on Saturday evening.

The out-of-control fire, which flared early on Saturday afternoon, poses an immediate threat to homes and lives as it tracks southeast, authorities say.

"It's too late to leave, leaving now would be deadly," Emergency WA said in its latest warning issued around 11.30am local time on Sunday.

An emergency warning had already been issued for the South West region, including Hester, Brooke and Bridgetown in the Shire of Bridgetown-Greenbushes.

"You are in danger and need to act immediately to survive. There is a threat to lives and homes," it said.

Emergency WA says 150 firefighters are battling the blaze, which has burnt out more than 2200 hectares.

Aerial support has been sent to assist ground crews and police. SES officers and ambulance personnel are also in attendance.

The Bridgetown Hospital emergency department has reopened and a community meeting will be held on Sunday afternoon at the nearby Bridgetown Leisure Centre.

Western Power says around 2500 customers in the South West and Great Southern regions are without power due to the bushfire.

Another emergency warning is in place in the Bruce Rock shire about 200 kilometres east of Perth, after a fire sparked there on Sunday morning.

Residents of Shackleton, Babakin and Bilbarin have been told to find shelter as it's now too late to leave.

An emergency warning remains for the coastal shire of Denmark, after residents were told to evacuate on Friday.

People in Shadforth and Scottsdale have been told to leave and seek safety if the way is clear.

WA Premier Mark McGowan on Saturday said multiple areas in the state continued to face "dangerous bushfire conditions with more hot weather forecast today and tomorrow".

The premier thanked firefighters for their efforts over the week and urged the public to follow advice from Emergency WA.

Australian Associated Press