Severe thunderstorm warnings issued for parts of Sydney and the Northern Rivers

The Bureau of Meteorology issued severe thunderstorm warnings for the Blue Mountains and Hawkesbury areas on Friday afternoon as wet weather returned to Sydney.

The warning was the latest in a series of alerts issued for across NSW after the bureau also told Wollongong, Bundeena, Kurnell, the Royal National Park and Stanwell Park to expect heavy rain.

Fresh storm warnings were issued for parts of Sydney on Friday afternoon.Credit: Bureau of Meteorology

Flash flooding is forecast in dozens of areas as two separate weather systems move slowly across the state.

The flood-hit Northern Rivers, the North West Slopes and Plains, Central West Slopes and Plains, and the Upper Western and Northern Tablelands districts were also forecast to receive heavy rainfall.

Lismore, Grafton, Walgett, Casino, Kyogle and Lightning Ridge were all expected to be affected.

“The State Emergency Service advises that people should keep clear of creeks and storm drains; don’t walk, ride your bike or drive through floodwater,” the bureau said.

“If you are trapped by flash flooding, seek refuge in the highest available place and ring 000.”

Residents were told to remain inside and to unplug all electrical equipment, including computers, and to avoid using phones during storm activity.

The final week of March is looking very wet for parts of eastern, western and northern Australia.Credit: Weatherzone’s Ben Domensino.

The warnings came as massive rainfall continued in the state’s north and a 72-year-old man died in floodwaters in the Northern Rivers.

Police say the man, who was yet to be formally identified, had attempted to cross a flooded road on foot in Coaldale, 35 kilometres north of Grafton, on Thursday.

The SES had already moved more crews into the Northern Rivers area and activated an incident management team in Grafton to provide additional support to a region already battered by recent flooding.

“The Australian Defence Force (ADF) are continuing to provide assistance, including moving over 200,000 sandbags and other equipment to the NSW SES warehouse [on Wednesday], in readiness for use across the state,” the SES said in a statement.

“Additional field response capability, including flood rescue and storm damage teams are also being deployed, supported by additional resources from our partner agencies.”

There are various flood warnings in place for the Narran and Culgoa rivers, as well as for properties along the Bellinger, Nambucca and Severn rivers. Wollombi Brook in Bulga and both the Birrie and Bokhara rivers could also see flooding.

The rainfall comes as a result of two systems moving across NSW – an inland trough and a coastal trough.

Weatherzone meteorologist Joel Pippard said the state’s Mid North Coast and the Northern Rivers areas will see the most rain on Saturday.

“With up to 40 millimetres a day for four days in a row expected, that builds up to a flood risk,” he said.

“We are just at the start of this event. In that inland area, in particular, it’s still very saturated, those inland rivers take a lot longer to go down and are much slower than coastal rivers.”

Mr Pippard said residents in alert areas should prepare for action.

“Pay attention to the warnings and then also enact a back-up plan if things go south,” he said.

Sydney is expected to get 25mm of rain on Friday and 10mm on Saturday, 30mm on Sunday and 15mm on both Monday and Tuesday.

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