More than 2,500 firefighters are battling 86 blazes across the Australian state of New South Wales.
Authorities say the conditions are worse than in 2009 when bushfires killed 173 people in Victoria on what's become known as 'Black Saturday'.
Temperatures have climbed above 45 degrees celsius in some parts.
Shane Fitzsimmons, Commissioner of the Rural Fire Service, says at this stage there are no reports of injury or death.
"We have got reports across a number of the fire grounds particularily those that are subject of an emergency warning that we are seeing property impacted and we're expecting to see property lost.
"At this stage we have got some uncomfirmed reports of homes being lost, sheds being lost, and machinery being lost."