'Prepare your homes': Months' worth of rain to fall in just days

A road in the NSW Hunter Region has been ripped apart as the state becomes inundated with rain.

Port Stephens Council posted a photo on Facebook of Foreshore Drive at Corlette on Thursday afternoon shredded and in pieces from heavy rainfall.

“This weather has caused multiple road closures and flooding incidents,” council wrote.

Some areas in the Hunter Region, including Williamtown and Norah Head, have already received more than 50mm since 9am Thursday.

Blacksmiths copped 50mm in an hour leading up to midday.

On Facebook, people were shocked by the destruction of the road.

“Yikes,” one woman wrote.

Another woman added “that’s why you don’t drive through floodwater”.

Warnings as areas cop 100mm in just hours

The rainfall has led to the Bureau of Meteorology issuing a warning on Thursday just before 5pm for heavy rainfall and damaging winds for Mid North Coast and parts of Northern Rivers, Hunter and Northern Tablelands Forecast Districts.

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BOM said heavy rainfall has already caused flash flooding in the Hunter.

“Increased rainfall rates about areas of the Mid North Coast are likely to continue to develop into Friday as a low are forecast to form off the Mid North Coast, shifting south as the low moves down the coast.

“Intense rainfall which may lead to dangerous and life-threatening flash flooding may develop in areas of the Mid North Coast and northern Hunter districts as continued rainfall impacts the region. Roads are likely to be cut off by water, and there will be an increased risk of landslips over this period.

“Damaging winds, averaging 60 to 70 km/h with peak gusts in excess of 90 km/h are likely to form on Friday along the coastal fringe as the low develops in the Mid North Coast, with the area of impact moving south by the evening.”

Seven Oaks received 202mm of rain in the six hours leading up to 4pm Thursday while Kempsey Airport was drenched by 138.8mm in the six hours up to 3.18pm, according to BOM.

WeatherZone meteorologist Ben Domensino said Walgett and Dubbo in NSW’s west have had the most rain in four to five years each received 65mm in the 24 hours up to 9am Thursday.

NSW SES Lake Macquarie Unit said it has already received 50 calls for help with most of them in regards to flooding “due to excess water run off”.

Heavy rainfall far from over

BOM meteorologist Jackson Browne said the wet weather “will likely continue into Saturday” as it moves south towards the Sydney basin and the Illawarra Region.

“Strong moist easterly flow in the Tasman Sea is pouring onto the NSW Great Divide with a coastal trough forming providing the focus for every rainfall,” Mr Browne said.

“Further assistance is provided from an upper low to the west.

Mr Browne said a coastal trough in the northern half of NSW will deepen later on Thursday with an embedded low becoming a “major focus” for the weather.

“Widespread totals of 100 to 300mm are likely with greater totals dependent on the movement of the coastal low,” he said.

Sky News Weather meteorologist Alison Osborne said there is some uncertainty about the rainfall totals across the weekend but Sydney and northeastern Victoria could experience flooding.

“With 150-300mm forecast in the northern half of NSW for some that will be almost a month’s worth of rain in just a few days,” she told news.com.au.

“In the outback there could be many months’ worth of rain in the next few days.”

Kempsey could receive a further 150mm on Friday and 70mm on Sunday while Coffs Harbour could cop three consecutive days of 80mm or more.

As the system moves south, Sydney is in for a wet Saturday with up to 120mm forecast. That's after a wet Friday of up to 50mm of rainfall.

Wollongong is forecast to cop more than 260mm in the three days from Friday onwards with Saturday a possible total of 200mm.

Mr Domensino said a forecasting model between Thursday and Wednesday next week shows more than 50mm could fall “in parts of every state and territory during the next seven days”.

Some places could receive “several hundred millimetres”, he said.

“This rain event will be the result of several weather features all aligning over Australia to create an ideal environment for widespread and significant rain,” he said.

Queensland also copped a drenching on Wednesday with hundreds of residents in the Central Highlands told to evacuate.

NSW SES chief superintendent Greg Swindells told The Guardian people should reconsider travelling in the current conditions.

“If it’s not required, put it off, and perhaps stay home and prepare your homes with any information that we give,” he told The Guardian.

“Never drive, walk or ride through floodwaters … it doesn’t matter how experienced you are as a driver or how big your vehicle may be, we can’t guarantee the integrity of floodwaters on road surfaces.”

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