UPDATE: MORE than 200 firefighters are battling a bushfire in Western Australia's southwest, where homes have been destroyed.

Lightning strikes on Tuesday afternoon triggered 16 bushfires in the region.

Homes and lives in Greenbushes came under threat on Wednesday afternoon and an emergency warning remains in place for the town, while Bridgetown and Balingup are subject to an "advice" alert, which means there's no immediate danger but residents need to keep abreast of the situation.

A homestead in Southampton, 12km south of Balingup and built in 1862, burnt down yesterday and a house some 900m away was also destroyed.

A third home on a farm has reportedly been destroyed while the Southhampton Bridge over the Blackwood River has been badly damaged.

The fire crossed the river yesterday and is moving in a north-easterly direction.

Shire of Bridgetown and Greenbushes president Brian Moore today said difficult terrain was making the firefighting effort challenging, but emergency services personnel had told him they made good progress overnight.

"The beauty of Bridgetown is the hills, the valleys and the steep terrain, and that's also our biggest enemy at this time of the year," he told ABC radio.

"It depends today on the heat and the wind."

Mr Moore said the community had dealt with a major fire in 2009 and was coping well.

Community meetings will be held at 10am (WST) at the Bridgetown Recreation Centre and at 11am (WST) at the Greenbushes Hall.

A "watch and act" warning is also in place for the Kin Kin area east of Manjimup, where a bushfire is burning towards Muir Highway and may threaten lives and homes.

That blaze has burnt through about 800ha of bushland.