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Hail as big as 4cm has smashed homes and cars in the NSW Hunter Region amid warnings of another evening of severe storms, with damaging winds also set to sweep in for Boxing Day night.
Cars, skylights, roof tiles and windows have been shattered by hail, and more than 50 people called for help in under an hour in Maitland and Rutherford.
Earlier, SES Assistant Commissioner Sean Kearns from the SES issued a warning about more wild weather, with volunteers on standby for a third day.
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"We are asking people to be aware, particular as these storms roll in," Kearns said.
"We may see a recurrence of the weather experienced on Christmas Eve and Christmas Day, with potential threats of damaging winds, large hail, and intense heavy rainfall."
In Sydney, more than 75,000 lightning strikes have been detected since yesterday.
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Earlier, the Bureau of Meteorology said it had "concerns" winds of up to 90km an hour could hit, along with hail as big as 2cm in size forecast.
Sydney, Newcastle, the Hunter Region and Central Coast are in the firing line, as the east coast continues to get a Christmas battering.
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Kearns said crews attended over 500 calls on Christmas Day, mostly on the NSW South coast and areas close to Forbes after storms.
"We saw a severe thunderstorm with large hail hit the regional community of Grenfell where we saw over 50 calls for assistance due to the damage the hail called," he said.
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https://twitter.com/BOM_NSW/status/1739460299080573173
Over Christmas, flash flooding also hit a caravan park in Kiama, with knee-deep water, he said.
"What we do know is these severe thunderstorms can lead to a large amount of rain in a short time."
A total of 156mm fell in three hours on the South Coast on Christmas Day, he said.
He reminded people never to drive through flood water.
"Flooded roads can be very deceiving. What may not look like much, the roadway may be actually washed away," Kearns said.
Hundreds of volunteers from the SES have given up Christmas to help deal with the wild weather.
Angus Hines from the BOM warned storm activity will build again into the evening along the whole of the east coast.
However he said Queensland and Victoria would likely be worst affected.
Rain and storms are also forecast for Wednesday – but that should be the last of it.
"By and large we're starting to see the end in sight for this thunderstorm outbreak." Hines said.
Victoria and South East Queensland have also been hit by Christmas Day storms, with a woman killed by a falling tree on the Gold Coast and a man dead after a tree branch fell in regional Victoria.
A storm on Christmas Eve saw dozen of people rescued from flash floods in Sydney's Eastern Suburbs, with flights cancelled.
But Christmas Day in the city was mostly a sunny 24C, with thousands flocking to beaches.
