WA bushfire threat weakens further

A bushfire in Western Australia's Great Southern region has weakened further, with the blaze now contained and under control.

A watch and act alert has been downgraded to an advice for parts of Marbelup in the City of Albany, the Department of Fire and Emergency Services says.

There is a lot of smoke in the area and residents have been told to remain alert in case the situation changes.

"The fire is predominantly stationary within the containment lines, however, a small section is still burning in vegetation near the Marbelup Creek," DFES said.

Firefighters are strengthening containment lines, patrolling the area and mopping up.

Some road closures remain in place and drivers have been asked to avoid the area.

The blaze, which started near the intersection of Marbelup North Road and South Coast Highway on Wednesday afternoon, has burnt 306 hectares.

The cause of the fire is unknown.