Australia urged nearly a quarter of a million people to evacuate their homes on Friday and prepared military backup as authorities said the next few hours could be “very, very challenging” even as rain poured down in some parts.Defense personnel stood ready to move to bushfire grounds if conditions became extreme, Prime Minister Scott Morrison told reporters, as soaring temperatures and erratic winds create dangerous conditions.“Even with rain in Melbourne, even with forecast better conditions next week, there is a long way to go in what has been an unprecedented fire event...and, of course, we know that we have many weeks of the fire season to run,” Daniel Andrews, the premier of Victoria, told a televised briefing.“The next few hours are going to be very, very challenging.”While the winds are expected to move through by Saturday morning, Andrews urged residents to stay on high alert and leave the community “if you are told to”.Authorities sent emergency texts to 240,000 people in Victoria, telling them to leave. People in high-risk regions in New South Wales and South Australia were also urged to think about leaving, but officials did not say how many.Since October, 27 people have been killed and thousands subjected to repeat evacuations as huge and unpredictable fires scorched more than 10.3 million hectares (25.5 million acres) of land, an area roughly the size of South Korea.In the coastal town of Eden in New South Wales, where the alert status was upgraded to ‘watch and act’ on Friday evening, smoke filled the horizon as winds blew smoke and ash.Shereen and Kim Green, who live on a farm with three houses and 50 cattle just outside Eden, were racing to fill two 1,000-litre tanks of water.“This is to put out the spot fires and we’ll be staying up all night to defend our property,” said Shereen, as the wind shook her utility vehicle. “We’re taking the opportunity while we can.”Sitting under the town’s watchtower, another resident Robyn Malcolm said: “If it all goes wrong, we’ll dash down to the wharf and get on a tugboat.”