Fresh rain warnings as BoM says flooding in NSW ‘to continue for months’

<span>Photograph: Jason O’Brien/AAP</span>
Photograph: Jason O’Brien/AAP

New South Wales is bracing for another week of thunderstorms, gusty winds and renewed flooding, with authorities warning flooding in some areas is expected to continue for several months.

The wet weather was expected to return to south-western parts of the state from Monday afternoon, deepening throughout Tuesday and Wednesday as the trough moved across to the coast.

The Bureau of Meteorology said expected rainfall totals were lower than the torrents of rain that battered the state over the weekend – isolating communities and claiming the life of a child. But the bureau warned renewed river rises and escalated flood warnings were possible in already saturated regions.

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“Severe storms may produce damaging wind gusts, localised heavy rainfall and large hailstones.

“Communities should be aware that with catchments wet and many dams at capacity, waterways are very sensitive to any future rainfall, and flooding is expected to continue for several months.”

Jane Golding, a senior forecaster said the rainfall would intensify towards the South Australian border on Monday evening, before a low pressure system developed, bringing widespread showers for the southern half of the state.

“There’s a lot of moisture in the atmosphere so there’s the potential for severe storms out that way and flash floods,” she said.

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She warned people needed to be alert

“For the next few days the rainfall totals might not be a lot but it’ll fall so intensely, it’s hard for the ground to absorb it at the moment, it ponds really easily,” she said.

“We’ll see a pretty similar summer to what we saw last year, more wet days than normal, [but] because the catchments are so saturated they’re going to flood a lot more easily than last year.”

Twenty-two flood warnings remained active for saturated catchments on Monday afternoon, while major flooding was still occurring on the Namoi, Macquarie, Bogan, Lachlan and Narran rivers.

Communities were bracing for the worst.

In the state’s north, the townships of Wee Waa and nearby Warren remained cut off by road access after heavy weekend falls, with emergency services using aircraft to deliver water, medicine, food and other supplies.

The Namoi River at Warren was expected to sit above the major flood level of 9 metres into Tuesday, while at Wee Waa, the river was expected to remain above major flood levels until Friday.

The cotton town is protected by an 8km levee, however the drenching over the weekend destroyed some local infrastructure.

More than three dozen roads remained shut to all traffic across Narrabri shire on Monday afternoon, including parts of the Kamilaroi Highway.

“Further rainfall is forecast from mid this week, which may result in renewed river level rises,” the BoM warned.

In the nearby town of Gunnedah, the Namoi River had recessed to minor flood levels after peaking at 8.24 metres on Saturday morning. NSW State Emergency Service (SES) were on the ground over the weekend assessing the damage and assisting with sand bagging.

Farther north towards the Queensland border, “renewed and prolonged” flooding was continuing along the Culgoa, Birrie, Bokhara and Narran rivers.

Golding said Thursday would be the “wettest day” for Sydney, with in excess of 10mm predicted, while showers and storms would linger from Tuesday until the end of the week.

The SES was moving vehicles and boats into flood prone areas, preparing for “busy months ahead”, after the declaration of a rare third consecutive La Nina.

In the 10 days to Saturday, emergency services fielded more than 800 requests for assistance across the state, including nearly 60 rescues from floods.

On Saturday afternoon, NSW Police recovered the body of a five-year-old boy after he was swept away in flood waters near Tullamore in the state’s central west.

He was separated from four family members when their car was submerged in flood water near Tullamore on Friday evening.

The first responders found two younger children and their parents clinging to trees. They said the boy’s parents were able to remove restraints from two younger children in the car, but weren’t able to free the boy.

The NSW premier, Dominic Perrottet, said the death was “incredibly tragic”.

SES Assistant Commissioner, Nicole Hogan, said Central West and North West regions would need to remain on high alert throughout spring.

“We are asking people, particularly with the school holidays, to prepare their route, [and] know where they’re going ahead of time … and if they are camping on the side of a river, to really be aware of their surroundings,” she told the ABC on Monday.