NSW weather: communities brace for flooding as heavy rainfall returns to state

Communities in New South Wales hit by heavy flooding earlier this year are bracing for days of torrential rain, as the east coast prepares for an intense wet spell.

The Bureau of Meteorology has issued a severe weather warning for heavy rainfall for the Sydney metropolitan, Illawarra and central tablelands districts, as a surface trough is expected to remain stationary over the weekend.

Six-hourly rainfalls of between 80mm to 150mm are possible, with the warning of heavy rainfall likely to last into Sunday, potentially bringing with it flooding along the east coast.

Related: Unseasonal deluge to bring wet and windy end to Australia’s east coast winter dry spell

At least 50mm of rain is expected every day from Friday to Monday in Sydney, according to the BoM, with temperatures expected to stay between 11C and 19C.

It coincides with the start of school holidays in some states, throwing travel plans into chaos, and authorities have warned residents to reconsider any plans.

Jane Golding from the BoM said the focus of the system will be on Sydney, the Hunter and the Illawarra.

“It looks like the focus area, firstly, will be around Sydney and the Illawarra tomorrow,” she said. “So we’re expecting some locations over the next few days and even tomorrow could see what they would normally see in the entire month of July fall in one day.

“So certainly heavy rainfall and there will certainly be impacts from that starting tomorrow.”

Golding said that landslips and flash flooding were also possible.

“… We know that the landscape is vulnerable at the moment and the water can move quickly down the slopes and through the waterways, so flash flooding, riverine flooding and landslips.”

The BoM said there is potential for an east coast low to develop off the coast overnight Sunday or early Monday, prolonging the heavy rainfall event into early next week.

If the low does form, the BoM said damaging wind gusts could become a risk late on Sunday and early Monday, depending on the location and strength of the low.

The BoM warned that the heavy rain could increase “the potential for landslides and debris across roads”.

Minor to major flood warnings have been issued for parts of the mid-north coast, including along the Colo, Hawkesbury, and the Upper and Lower Nepean rivers.

Minor to moderate flooding could also hit the Goulburn and Upper Hunter rivers, the Shoalhaven River and St Georges Basin.

The BoM has advised residents who live along these rivers to stay up to date with weather forecasts and of any potential flood warnings.

There are also minor flood warnings for the Lachlan River, and minor to moderate warnings for the Culgoa, Bokhara and Darling rivers.

“People in low-lying parts of these areas should prepare for flooding by taking measures to protect their homes against water damage,” the NSW SES said.

“Local roads and recreational areas may be inundated by deep and/or fast-flowing flood waters. Residents should also prepare for possible evacuation by locating and packing valuable items and documents.”

The rain is expected to persist until at least Wednesday, but temperatures are expected to rise by then, reaching at least 20C from Tuesday onwards.

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It comes as Sydney records its coldest start to winter in 30 years, with temperatures in the first week of June failing to reach more than 18C.

The city recorded its driest June since 2005, marking the end of the La Niña period that brought with it record levels of rainfall.

The BoM declared La Niña over on 21 June, but warned that there was still a 50% chance of another La Niña event forming again during 2022.