Thousands of people had to be evacuated across the region after the massive storm hit large areas of New South Wales and the Australian Capital Territory on Saturday and Sunday, uprooting trees and leaving thousands more without power.
Residents remain under threat as flood waters rise in the wake of the storm, closing roads and bridges and, flushing out dangerous wildlife.
"We haven't just seen a lot of rain, we've had very strong winds and a lot of trees down, and the power has been out for up to a day in some areas," NSW State Emergency Services (SES) spokesman Matt Reeves told CNN.
"It's very widespread, it certainly hasn't been a localized event, so really from the north coast of NSW literally to the south coast."
The storm has now moved south through Victoria to Tasmania, where record floods have already been recorded.
Three dead, one missing
The storm has left a trail of destruction in its wake, with three men killed in three separate incidents in NSW and the ACT.
Two men were confirmed dead by NSW Police on Monday after their cars became trapped in flood waters in different parts of the state. One man died at Bowral, in the state's south, and another to the southwest of Sydney, according to a statement issued by the NSW Police
, which noted that the men were yet to be identified.
"It is a tragedy these two lives have been lost," acting Assistant Commissioner Kyle Stewart said in an accompanying statement.
"We simply do not know how either of these two men came to be in the flood waters. But what we know is that their deaths show just how dangerous flood waters are."
Another man was also confirmed dead in the nation's capital Canberra, in the ACT, on Monday, after rescue teams found his body trapped in a car in a swollen river, according to a statement on the ACT police website
Police said they had been alerted to a car caught in flooding in the Cotter dam but that, "due to the severe weather conditions, fast-rising and moving water, the man was unable to be rescued."
Police in both states are urging motorists to beware of flood waters and avoid entering areas that were known to be inundated.
Another man is missing after he was spotted in distress while swimming at Sydney's Bondi Beach Monday afternoon, New South Wales police said.
A search and rescue operation involving boats and a helicopter was launched, but was suspended after several hours due to fading light. The search will resume at first light Tuesday, police said.
The massive storm caused more than 86,00 homes in the region to lose power and led to widespread damage to infrastructure, uprooting trees and cutting off roads and bridges, Reeves said.
"From a NSW perspective we are certainly seeing some major flooding in the north of the state around Lismore, and we had over 2,300 people evacuated from their homes in Lismore over the last few days."
Reeves noted that the biggest high tide of the year had also exacerbated the impact of the storm on Sydney's northern beaches, with more than 700 people evacuated from Narrabeen and Collaroy.
The tide caused extensive erosion to beaches across the city, and a number of multi-million dollar homes along Collaroy Beach are now in danger of collapse.
Snakes in the wake
Although the immediate threat from the storm has receded, water levels in rivers across NSW and Victoria continue to rise. Tasmania is also inundated, with flooding at record levels and flood warnings issued for seven rivers in that state, according to the Australian Bureau of Meteorology.
The rising waters have flushed out further dangers, with Australian freelance cameraman, Jason Webster
, spotting an enormous red-bellied black snake
on a bridge in the Sydney suburb of North Richmond, next to the Hawkesbury. Webster estimated the snake, which can be dangerous, was about 1.5 meters (5 feet) long.
Reeves said that although the cleanup has started in the NSW region, the full extent of damage caused by the storm won't be known for a number of days.
"Where we've had flash flooding it's predominantly subsided but where we have inundations from river systems and lakes it's going to probably be another couple of days before we see that water subside and then crews can get in there proper to start that recovery process," he said.