BRISBANE, Australia— Emergency sirens blared across Australia's third-largest city Wednesday as floodwaters that have torn a deadly path across the northeast poured into an empty downtown, swamping neighborhoods in what may be Brisbane's worst flooding in 100 years. Australia Flood 465 5 (photo credit: Associated Press) Australia Flood 465 4 (photo credit: Associated Press) Australia Flood 465 3 (photo credit: Associated Press) Australia Flood 465 2 (photo credit: Associated Press) Australia Flood 465 1 (photo credit: Associated Press) Australia Flood 1 (photo credit: Associated Press) Australia Flood 2 (photo credit: Associated Press) Australia Flood 3 (photo credit: Associated Press) Australia Flood 4 (photo credit: Associated Press) Australia Flood 5 (photo credit: Associated Press) Australia Flood 6 (photo credit: Associated Press) Australia Flood 7 (photo credit: Associated Press) Australia Flood 8 (photo credit: Associated Press) Australia Flood 9 (photo credit: Associated Press) Australia Flood 10 (photo credit: Associated Press) The surging, muddy waters reached the tops of traffic lights in some parts of Brisbane, and the city's mayor said at least 20,000 homes were in danger of being inundated.RELATED:Brazil gov't says 100,000 displaced by floodsPhoto gallery: Heavy rains, strong winds batter Middle EastAt least 22 people have died and more than 50 are missing elsewhere in Australia's northeastern state of Queensland since drenching rains that began in November sent swollen rivers spilling over their banks, inundating an area larger than France and Germany combined. Brisbane, the state capital with a population of 2 million, is the latest city to face down the waters.On Wednesday, Brisbane residents who had spent two days preparing took cover on higher ground while others scrambled to move their prized possessions to the top floors of their homes Some stacked furniture on their roof.