Cars, roofs ripped off as polar blast hits
Damaging winds have also torn the roof off a nursing home in NSW as wild weather lashes the state.
At around 10am emergency services were called to Wescott Presbyterian nursing home in Stockton following reports a section of roof had been ripped off by a massive wind gust.
Around 30 residents were evacuated and there were no reports of injuries.
SES and NSW Fire and Rescue crews are working to remove the debris.
The wild weather is also causing destruction in Victoria. Melbourne has been smashed by ferocious winds of up to 120km/h, with a pier snapping off and washing away in large swells.
A local man told the Herald Sun newspaper that about 10m of the structure was ripped off.
"These weather conditions I would describe as cyclonic - extreme winds. The Frankston Pier - what we can see is the end of the pier - has come away with the force of the wind and the waves," he said.
In the state's Yarra Ranges, a large fallen tree crushed a car and trapped four people inside, with two children rushed to hospital - one in a critical condition.
A rescue chopper took the injured child to Royal Children's Hospital with serious head injuries, while a man in the vehicle was taken to the Alfred.
Along with dangerous winds, temperatures have also been sent plummeting in the country's east.
The Bureau of Meteorology warned ACT residents they may see some snow around the area and the wind chill will make it feel even colder than it is.
A small dusting of snow was seen on the ranges around Canberra today, but there has also been a few reports of it swirling around the air in the city.
A "polar blast" bringing extreme gusts and plunging temperatures is hitting much of Australia's east coast today and will continue throughout the weekend.
The Bureau of Meteorology has issued a number of severe weather warnings covering New South Wales, Victoria and South Australia.
Authorities are urging motorists to take care due to the risk of fallen trees.
In Sydney and Melbourne, those flying today are being told to expect delays with a number of cancellations and diversions tipped.
Significant gusts have smashed Victoria, with Bureau senior forecaster Michael Efron saying winds of up to 120km/h have been recorded.
"We're actually seeing gale force winds across Port Phillip and down towards the Geelong region there are gusts of up to 90 kilometres and hour," Mr Efron told 3AW Breakfast.
Strong swells have caused part of the Frankston pier to snap off and wash away.
In NSW, a series of cold fronts that began crossing the country's southeastern parts yesterday will intensify today, generating "vigorous westerly winds", the Bureau said.
Damaging winds of up to 90km/h are likely, with warnings in place for the Southern Tablelands, Snowy Mountains, Illawarra and Southern Coastal Ranges, as well as the ACT, Blue Mountains and high country about Barrington Tops.
Greater Sydney will also see gusts of between 60-70km/h, peaking at up to 90km/h, the Bureau warned.
Winds are expected to build from midmorning on Friday and continue throughout the day and into the weekend.
Blizzards are likely for Alpine areas above 1500m.
In Sydney, the mercury is set to plunge to eight degrees overnight and only reach 17 degrees tomorrow and on Sunday.
Conditions in Victoria could get even more precarious, with severe westerly winds of up to 100km/h extending along the east Gippsland coast from midday.
Peak wind gusts may reach up to 110km/h about southern parts of the South West and Central districts, including the south eastern suburbs of Melbourne, the Mornington Peninsula and the west Gippsland coast.
The State Emergency Service warns motorists in Melbourne to take care, with dangerous wind conditions posing a hazard on roads.
The state's Alpine region above 1200m could see peak gusts up to 120km/h on Friday, with blizzards likely.
It's likely to be as cold as five degrees in Melbourne overnight, only reaching 11 degrees tomorrow and on Sunday.
Across most of NSW and Victoria, the extent of extreme winter weather could be the worst seen in at least three years.
In South Australia, the Bureau is also urging residents in the state's southeast to exercise caution in Adelaide, Murray Bridge, Kingscote, Victor Harbor, Meningie and Coonalpyn.
An intense low over Bass Strait is moving further eastwards and a second low in the Southern Ocean will move north to north-eastwards during Friday.
Damaging south-westerly winds of between 50-70km/h, peaking at up to 110km/h, are likely.
In Adelaide, Saturday will see a low of seven degrees and a maximum temperature of 13 degrees, with similar conditions on Sunday.
"This could be the strongest cold outbreak so far this winter," the Bureau's Michael Logan said.
"We'll see temperatures really plummet and snow levels down to 500m in Victoria and NSW and blizzard conditions in Alpine areas. It certainly is a real cold snap, now is the time to prepare."
REPORTERS OUTSIDE IN THE COLD
The expected severe conditions have made headlines this morning, with breakfast television covering the weather event widely.
Snow is falling at ski fields in NSW and Victoria, with reporters heading out into the wild to cross live amid flurries of white.
Sky News crossed to rugged-up reports in Melbourne and Sydney, as well as sports presenter Tim Gilbert in the snow, while the ABC's reporter on the ground resembled an Arctic explorer.
Channel 9's Today had a journalist out in Melbourne's ferocious wind at the crack of dawn, while Seven's Sunrise pulled its best puffer jacket out of the cupboard for its Sydney cross.
Meanwhile, this reporter went out for coffee earlier and can confirm that it is indeed cold.
WHY IS IT GETTING SO COLD?
Unusually warm temperatures has been a feature of Winter 2019 in Australia. In an average winter, cooler air from the Antarctic pushes into southern Australia bringing down the mercury and serving up wind and rain.
However, stubborn areas of high pressure have, for months, acted as a barrier to this polar air which has been unable to push very far into the mainland at all.
High pressure brings settled conditions and clear skies. In winter, that means warm days with maximums ways above the average. For instance, in Sydney 17C is the usual winter daily high, but this year it's been closer to 18C, while overnight lows are around three degrees warmer.
Clear skies also let that warm weather escape overnight which has led to lots of frost this year too.
But now, the high pressure appears to be losing its battle with the Antarctic conditions. It's heading north to more tropical climes, allowing unsettled conditions and cloud to make an appearance in the south. That will mean cooler days but, in some places, more average night time lows.