At least one home has been destroyed by a bushfire south of Perth after strong easterly winds pushed the blaze into the town of Waroona.

The fire was sparked by lightning on Thursday morning and began south of Forrington Heights in the steep terrain of the Darling Range to the town's east.

The Department of Fire and Emergency Services says one home has been confirmed lost, and there are also unconfirmed reports of other structures being damaged.

An emergency warning is in place for an area bounded by Nanga Brook Road, Hill Street, McLartey Street and Paganini Road.