Light rain and cooler temperatures brought relief on Monday to firefighters and residents battling fires across Australia, but forecasters warned that temperatures would rise again mid-week.

In the country's southeast, where blistering heat over the weekend fuelled fires which destroyed up to 20 homes, more than 1,000 people who were evacuated were to return to their homes, although resort towns such as Cooma and Jindabyne remained under threat.

But in the northwest, rain over the weekend brought little respite. Rescue workers were grappling with floods on Monday, following heavy tropical rains.

And authorities warned that after a month of wild fires in southeast Australia, many blazes were still out of control.

Some 80 blazes continue to burn across New South Wales, including one in the Royal National Park bordering the south-eastern suburbs of Australia's largest city, Sydney.

Back burning

"Firefighters are going to be taking advantage of the milder conditions today and tomorrow to work on containment strategies ahead of a return to hot, dry conditions around Wednesday," New South Wales state Rural Fire Service spokesman John Winter said on Monday.

Hotter weather is expected again mid-week

About 4,000 firefighters were engaging in a process known as back burning - creating firebreaks by deliberately scorching the earth with small fires to prevent the ground from burning again.

But so far emergency teams have prevented a repeat of last weekend's disaster near the federal capital, Canberra - where four people were killed and 530 homes went up in flames.

Bushfires continued to burn around Canberra but officials said no homes were immediately under threat.

Another fireman - a volunteer - died on Sunday, when three emergency vehicles collided while trying to protect the western town on Lancelin, 120 km (72 miles) north of Perth. At least four people were injured.

The fires have been fed by bone-dry conditions, following 10 months of El Nino-aggravated drought.