Sydney has received more rain than it usually receives in a year in only three and a half months, causing fresh floods in low-lying neighborhoods around the region.

In recent months, NSW has been plagued by a series of significant floods, with the Northern Rivers area being flooded twice in as many weeks and Sydney being drenched on a near-daily basis.

Due to the bad weather, key areas in the city's west, including Liverpool, have been warned that they may flood later in the day when overflowing rivers breach their banks.

There are enormous falls as far inland as Dubbo and Orange, as well as along much of the coast, throughout a broad expanse of New South Wales.

"The rain event has just started," said meteorologist Rob Sharpe.

With a lot of rain rushing into Australia's east, there's still a long way to go with this storm.

Nepean River flood exceeds the 1988 levels
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Sky News Chief Meteorologist Tom Saunders expressed "serious concern" for the Nepean River in Sydney's southwest and west as rainwater pelted parts of the city, as per News.com.

Flood levels are expected to exceed those experienced in 1998, which set a new record.

Officials from the NSW BOM and the NSE SES stated flooding in Menangle and Wallacia will be higher than it was last month and will be closer to the height observed in April 1998.

From March 2022, flooding in Camden is predicted to exceed the current level, with the Georges River also expected to flood in Liverpool and Milperra.

On Thursday, the Bureau of Meteorology (BOM) has issued a severe weather warning for the whole NSW coast between Newcastle and Bega, near the Victorian border.

Severe weather will come through the south coast

Over the next three days, at least 100mm of rain is expected in Sydney, the Blue Mountains, and throughout the south coast.

"However, totals of up to roughly 300mm are possible." As a result, flash flooding is a severe worry, according to Mr. Sharpe.

A number of variables have contributed to the torrential weather. The La Nina climatic phenomenon is still pushing warm, humid air toward the continent.

Simultaneously, cooler-than-normal air is high in the atmosphere, forcing warmer moisture to ascend and create clouds, which subsequently rain heavily.

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The highest annual rainfall recorded

With 537mm raining into the Observatory Hill gauge last month, Sydney experienced its wettest March on record.

This surpassed the previous high of 521mm for the month of March, set in 1942, as per North West Star.

According to the BOM's senior meteorologist Jonathan How, the record made it a "highly noteworthy month."

"What we do know is that Sydney has reached 1000 millimetres for the year for the second time on record," he added.

Observatory Hill had more than 114mm of rain in the 24 hours leading up to 9 a.m. on Thursday, and another 18.4mm in the four hours that followed, bringing the year's total to 1245.2mm.

The average annual rainfall is 1213.4mm.

The Central Coast, Greater Sydney, Illawarra, and South Coast have all been hit hard by heavy rains.

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